The breadth of a plate increases from one corner to other in a continuous manner. Breadth of the pla

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16 Jan 2014 Solve

The breadth of a plate increases from one corner to other in a continuous manner. Breadth of the plate changes from 10 cm. to 20 cm. and length of the plate is 50 cm., then area of the plate is

OPtion

1) 250
2) 860
3) 1455
4) 4800
5) 475
6) 500
7) 625
8) 750
9) 125
10)None of these

Solution

We can assume that the plate is formed of three geometries
First is a right angled triangle of two perpendicular sides 50 & 5 cm.
Second is a rectangle of dimensions 50 & 10 cm.
Third is a right angled triangle of two perpendicular sides 50 & 5 cm.
Total area of the plate is 1/2(50+5) + 50×10 + 1/2(50+5) = 750

Correct Option: 8 Best Solution (13)

Dr.Dipin Singh   11 years AGO

Area of plate = 10*50 + 50*(20-10)/2= 500+250=750 sq cms.

Like? Yes (8) | No (1)  

madanpal vishwakarma    11 years AGO

initaialy the the length is=50 and breadth = 10 cm
so area= l*b = 50*10=500 cm^2

now the breadth increased to 20 cm so the additional area increased is a right angled triangle

so increased area= 1/2* 50* 10= 250 cm^2
so total area = 500 + 250 =750 cm^2

Like? Yes (9) | No (5)  

KRISHNAN   11 years AGO

The Breadth changed from 10 to 20 cm and the height is 50cm

So the Area of the Trapezium is found by 1/2(a+b) x h
where a and b are the two breadths and h is the height
Therefore 1/2(10+20)x 50 = 750 cm is the area hence option 8 is the correct answer

Like? Yes (3) | No (1)  

Udhaya kumar   11 years AGO

(1/2)bh + lb
(1/2) * 50 * 10 = 250
50*10=500
500+250 = 750..

Like? Yes (2) | No (1)  

Sudipta Mukherjee   11 years AGO

width of one corner=10, another one is =20,
length=50,
it is a trapezium
so,area of the plate=1/2*(sum of parallel sides)*hight;
1/2*(10+20)*50=750 cm^2

Like? Yes (2) | No (1)  

Gurmeet Singh   11 years AGO

Required area=
50*10 + (1/2*10*50)= 750

Like? Yes (1) | No   

Srinivasa Vamsi Krishna Dodda   11 years AGO

Trepizoid area .5*[10+20]*50

Like? Yes (2) | No (1)  

Vijay Chauhan   11 years AGO

suppose first breadth is 10cm and length is 50cm...so area is 500cm...
now breadth of the plate is change only one side 10 to 20 cm...so become new triangle for that..10 X 50...
so its area is 250...so add 500 + 250 = 750

Like? Yes (1) | No (1)  

Naveen Pandey   11 years AGO

its a trapezium

Like? Yes (1) | No (1)  

Sukanya   11 years AGO

Split the plate into two parts.
The upper part is a right triangle with base 50 and height 10 so its area is 1/2*50*10=250
The lower part is a rectangle with length 50 & breadth 10 so its area is 50*10=500.
Area of the plate is 750.

Like? Yes (1) | No (1)  

ARJYA HALDER   11 years AGO

The above area can be divided into two parts, i.e,
1.A right angled triangle with height=10 cm & base=50 cm
2.A rectangle with length=50cm & breadth=10 cm.
Area of required figure is=
Area of triangle+Area of rectangle=
[(1/2)*10*50]+[50*10]=
750 cm^2
So, option 8 is correct.

Like? Yes (1) | No (1)  

VIKASH RAY   11 years AGO

The above area can be divided into two parts, i.e,
1.A right angled triangle with height=10 cm & base=50 cm
2.A rectangle with length=50cm & breadth=10 cm.
Area of required figure is=
Area of triangle+Area of rectangle=
[(1/2)*10*50]+[50*10]=
750 cm^2
So, option 8 is correct

Like? Yes (1) | No (1)  

Naveen Kumar   11 years AGO

area of trapezium=(1/2)*(sum of length of parallel sides)*height between these parallel sides

Like? Yes (1) | No (1)