A boy 1.4 m tall casts a shadow 1.2 m long at the time when building casts a shadow 5.4 m long. The

Surit Datta   9 years AGO

Cross multiply and solve for x.
1.4/1.2 = x/5.4
solving this we get
x = 6.3 m
so option 7
that's it.

Like? Yes (20) | No (1)  

Supriya Mondal   9 years AGO

Ratio of original height to the shadow height is=1.4/1.2=1.1667
So, original height of the building is= 1.1667*5.4
=6.3 m
So, option 7)6.3 m is the right answer

Like? Yes (5) | No   

Jay parmar   9 years AGO

1.4/1.2 = x/5.4
x = 6.3

Like? Yes (5) | No (1)  

shareef   9 years AGO

(1.4/1.2)*5.4 =6.3

Like? Yes (3) | No   

Yathiraj   9 years AGO

(1.4 * 5.4) / 1.2 = 6.3

Option 7

Like? Yes (2) | No   

ipsita   9 years AGO

let ABC and EDC are similar triangles with BC=5.4m DE=1.4m and EC=1.2m. equating AB/DE=BC/EC we get AB= height of the building as 6.3m

Like? Yes (2) | No   

Samyak   9 years AGO

As man's hieght /man's shadow = building's height/buidling's shadow
1.4/1.2 = x/5.4

therefor, x= 6.3 m

Like? Yes (2) | No   

nishi   9 years AGO

height of building/height of shadow=height of boy/height of shadow of boy
x/54=1.4/1.2
x=6.3

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RAKESH   9 years AGO

h = 1.4 * 5.4 / 1.2 = 6.3

Like? Yes (1) | No   

J.DHANDAPANI   9 years AGO

Let θ be the angle of inclination of ray of sun light . Therefore,Tanθ =height / base(shadow)
Tanθ = 1.4/1.2 , Tanθ = h/5.4 => 1.4/1.2 = h/5.4 => h=6.3m

Like? Yes (1) | No   

praveen kumar   9 years AGO

angle theta = inverse of tan(1.4/1.2)
=49.39
height of building = tan 49,39* 5.4 = 6.3 m

Like? Yes (1) | No   

SANTOSH SAHOO   9 years AGO

shadow : height
=> 1.2 : 1.4
=> 6 : 7
if shadow is 5.4 then height must be 6.3

Like? Yes (1) | No   

K S V S SRIHARSHA   9 years AGO

1.4 meters tall boy ---- 1.2 meters long shadow
? meters tall ---- 5.4 meters long shadow
on solving ? = 6.3 meters

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sravani   9 years AGO

1.4/1.2=x/5.4
x=6.3meters

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ANAND KUMAR   9 years AGO

let height of building be x
then,
1.4 : 1.2 = x : 5.4
x=6.3

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devendrachary   9 years AGO

6.3m

Like? Yes (1) | No   

Pranati Kundu   9 years AGO

let the angle be x
and the height be h
tan x=1.4/1.2=1.167
y/5.4=1.167
y=6.3 m

Like? Yes (1) | No   

MRITUNJAY   9 years AGO

1.4/1.2=x/5.4

x=6.3m

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sheikh shahrukh   9 years AGO

1.4/1.2=x/5.4
so
x=6.3m

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sompon temtheerakij   9 years AGO

The height of the building = 1.4/1.2*5.4 = 6.3 m.

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ABHINAV PUSHPAM   9 years AGO

(1.2/1.4)*5.4= 6.3
Option 7

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sindhura   9 years AGO

1.2x=5.4*1.4 => x=6.3

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Deb Das   9 years AGO

tan A=1.4/1.2
now hight=7/6*5.4=.9*7=6.3

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Kaju Gupta   9 years AGO

1.4/1.2 = x/5.4
x=6.3

option 7)

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ramakrishna   9 years AGO

1.4/1.2=x/5.4
x=6.3

Like? Yes (1) | No   

CHAYAN KUMAR   9 years AGO

let x be the height of building then according to triangle similarity property (1.4/x)=(1.2/5.4)
x=6.3

Like? Yes (1) | No   

Jeevitha   9 years AGO

1.2/1.4=h/5.4
h=6.3m

Like? Yes (1) | No   

RAHUL KUMAR   9 years AGO

1.4/1.2 *5.4=6.3m

Like? Yes (1) | No   

Anshul Garg   9 years AGO

According to trigonometry,
tanx = h/b
So, 1.4/1.2 = x/5.4 (x is height of building)
Now, Solve for x and we get 6.3.

Like? Yes (1) | No   

Saurabh   9 years AGO

tan x = 1.4 / 1.2 ------ eq 1
tan x = H / 5.4 ------ eq 2

using 1 and 2

1.4/1.2 = H/5.4

H= (1.4 * 5.4)/1.2
H=6.3

Like? Yes (1) | No   

kumar chayan   9 years AGO

(1.4/x)=(1.2/5.4)
x=6.3

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Meenakshi   9 years AGO

Let h be the height of the building
1.4/1.2=h/5.4
=>h=1.4*5.4/1.2
=>6.3 m

Like? Yes (1) | No   

Srinivas   9 years AGO

tan @ = 1.4/1.2 = 7/6
and Tan @ = x/5.4
=> 7/6 = x/ 5.4 =>x = 6.3

Like? Yes (1) | No   

AMIT KUMAR   9 years AGO

by unitary method
1.2 --- 1.4
1 ---- 1.4/ 1.2
5.4--- (1.4/1.2)* 5.4= 6.3

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Ajinkya Kulkarni   9 years AGO

6.3

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madhusudhana   9 years AGO

6.3 m

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vaishali rathore   9 years AGO

tanA=1.4/1.2 tanA=L/5.4
1.4/1.2=L/5.4
L=6.3m

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Bheemaray s vangi   9 years AGO

tan(angle)=(1.4)/(1.2)
angle remains same for both building and man
therefoe
height of building=tan(angle)*5.4=
((1.4)/(1.2))*5.4=6.3

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KUMAR HARSH   9 years AGO

let hieght=x
x/5.4=1.4/1.2
x=6.3

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MD Sohail Ansari   9 years AGO

1.4/1.2 = x/5.4

Solve for x

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mohsin   9 years AGO

Height/Shadow: 1.4/1.2: X/5.4

x= (1.4*5.4)÷1.2
x=6.3

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SAGNIK PAL   9 years AGO

tan x = 1.4/1.2 eq1
tan x = H/1.4 eq2
using 1 and 2

1.4/1.2=H/5.4
H= 6.3 Ans:

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Narasimha Teja   9 years AGO

The length of shadow is proportional to the object casting the shadow.

Like? Yes (1) | No   

jalaj   9 years AGO

ratio of height to the shadow and ratio of the height of building to the shadow is same at a time

=>1.4/1.2=x/5.4
=>x=6.3m

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Daras rani   9 years AGO

h_boy/s_boy = h_building/ s_building.
so, height of the building = (1.4/1.2) /5.4

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rohit Prakash gupta   9 years AGO

1.4/1.2=x/5.4
x=(1.4*5.4)/1.2
x=6.3
hence height of the antenna is 6.3m

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Thirupathi Reddy   9 years AGO

(x+1.4)/5.4=1.4/1.2
then x+1.4=6.3

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Thirupathi    9 years AGO

(x+1.4)/5.4=1.4/1.2
then x+1.4=6.3

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SUSHANT KUMAR   9 years AGO

1.4/1.2=x/5.4

x=6.3

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Hemant Pathak   9 years AGO

1.4/1.2=x/5.4

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arpitmittal   9 years AGO

ratio of shadow upon actual height remain same for ever object at same time. therefore 1.4/1.2=x/5.4

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Devendra Marghade   9 years AGO

Height of the building= 5.4*1.4/1.2 = 6.3

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k asreef basha   9 years AGO

1.4/1.2=x/5.4

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HANUMANTHU SAI SRUJAN   9 years AGO

(1.4/1.2)*5.4
=6.3

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ashwani bhati   9 years AGO

tanx=1.4/1.2 ....equation 1
tanx=h/5.4..equation 2



h is height of building.
no solving both equation ans 6.3

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NESAB JAFAR   9 years AGO

m1/s2=m2/s1

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akanksha jain   9 years AGO

in case of boy
tan x=1.4/1.2----1

as x(angle of inclination) will be same in case of man and building
so:

in case of building
tan x=height/5.5-----2
equating 1 and 2
we get height = 6.3

Like? Yes (1) | No   

MANGESH V . MASRAM   9 years AGO

cross multiply
take answer as X and solve.
x=1.4*5.4/1.2=6.3

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Divya jain   9 years AGO

at the same time both casts the same ht-shadow ratio
therefore
1.4/1.2 = x/5.4
on solving we get
x = 6.3 ans

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RAJAN   9 years AGO

height of building= 1.4*5.4/1.2=6.3m

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aman   9 years AGO

Using trigonometry

Tan & = 1.2/1.4
Tan & = 5.4/x
x = 6.3 m

& is angle of sun on top ..

We can also use this
1.4m height shadows 1.2m
Then x,height shadiws = (5.4*1.4)/1.2 = 6.3m

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Tarun   9 years AGO

1.4/1.2 = x/ 5.4

where x is height of building

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Bikash sahu   9 years AGO

for 1m. long shadow :1.4/1.2=1.16

for5.4m long=1.16*5.4=6.3

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ABINAYA R   9 years AGO

we can solve this problem by using the chain rule
if a boy have 1.4 m tall&1.2m shadow same as building have the shadow at the 5.4m long.so by using chain rule we can use

1.2 1.4
5.4 x
we have to cross mutiply to get the x as the height of the building
so
1.4*5.4=1.2*x
x=(1.4*5.4)/1.2
x=6.3

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saranya.s   9 years AGO

1.2 m long = 1.4 m tall
5.4 m long= ? X
1.2 x= 7.56
x= 6.3 m

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Abhishek Porwal   9 years AGO

1.4/1.2=h/5.4
h=6.3

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Madhumoy Gope   9 years AGO

The height of the building is=(1.4/1.2)*5.4 m=6.3m
So,option (7) is correct

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lakshmi narayana   9 years AGO

by 1.4& 1.2 we can find angle
where angle =49.39, therefore caluculated with this angle height of the building is 6.298.... =6.3

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vaishnavi   9 years AGO

h1/shadow=h2/shadow

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RAKESH ARYA   9 years AGO

1.4/1.2 = x/5.4
=> x= (1.4/1.2)*5.4 = 6.3

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RAVI KUMAR   9 years AGO

let x be the height of building
1.4/1.2=x/5.4
=>x=7*5.4/6
=>x=6.3

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ramakrishnateja   9 years AGO

given that the 1.4m boy casts a shadow 1.2m long. then let x m be height that casts 5.4m long shadow. so, h1/x=s1/s2
1.4/x=1.2/5.4. x=1.4*5.4/1.2=6.3

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sreenithirajkumar   9 years AGO

tan=1.4/1.2. =.7/.6
tan=x/54.
let x is the height of the building
x=(.7/.6)*5.4=6.3

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sandeep kumar   9 years AGO

1.4/1.2= height of the building/5.4



ANS=6.3m

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PUJA MUKHERJEE   9 years AGO

height=(1.4*5.4)/1.2=6.3

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sourav pal   9 years AGO

1.4/1.2=h/5.4
h=6.3

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upendra singh chahar   9 years AGO

1.4/1.2 = x/5.4 (here x is the height of building)
x = 6.3

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sanuj   9 years AGO

tanA=(1.4/1.2)
A=49.39
and
similarly, (x/5.4)=tan(49.39)
solving,
=>x=6.3m

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PRASHANT KUMAR   9 years AGO

as they form congruent triangles right triangles with boy 'h' and the bulding 'H'
so H=(B/b)*h

where B and b are the respective bases of the triangles
=(5.4/1.2)*1.4
=6.3

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Paras Jain   9 years AGO

1.4/1.2 = h/5.4 => h = 6.3m Ans.

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sam   9 years AGO

1.4/1.2=h/5.4
solving this to get height=6.3m

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Manoj   9 years AGO

1.4/1.2=x/5.4

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Abhishek Kumar Kushwaha    9 years AGO

because boy cast its 85.71% of shadow of his height similarly at the same time building will also cast 85.71% of its height i.e., 6.3m. So the height of the building is 6.3m.

Like? Yes (1) | No