M4maths
Maths Puzzle
Numerical Ability
Ratio and Proportion
the sum of three numbers is 102.if the ratio between the first and the second be 2:3 and the second and the third be 5:3, what is the second number?
Read Solution (Total 6)
-
- 2*5/3:3*5/3:3=10/3:5:3
10:15:9
(10+15+9)x=102
x=3
15x=45 - 8 years agoHelpfull: Yes(4) No(0)
- 45
Ratio of first and second = 2x:3x and second and third= 5x:3x
So ratio of all the three numbers= (2*5)x : (3*5)x : (3*3)x = 10x : 15x : 9x
As sum 10x+15x+9x= 102 , 34x= 102 , x= 3
So the numbers are 30, 45, 27 - 8 years agoHelpfull: Yes(3) No(0)
- a:b=2:3 & b:c= 5:3
a:b:c=10:15:9
a = (sum of all three numbers/a+b+c) * a; (102/34) *10=30
Similarly b= 45 - 6 years agoHelpfull: Yes(1) No(0)
- Ans:45
a : b =2:3
b :c =5:3
A: b: c = 10 :15:9
Let the ratios be x
10x:15x:9x
Now add the ratios =10x +15x +9x
=34x
Now 34x =102
X =3
2nd no.will be 15 x= 15×3=45 - 6 years agoHelpfull: Yes(0) No(0)
- Since a:b = 2:3
& b:c = 5:3
we have to make value of b equal in above equation by multiply i by 5 & ii by 3,we get
a:b = 10:15
b:c = 15:9
therefore a:b:c = 10:15:9
now, 10x + 15x + 9x = 102
34x = 102
x = 3
therefore second number = 15x = 15*3 = 45 - 5 years agoHelpfull: Yes(0) No(0)
- a:b=2:3, b:c=5:3
a:b:c= 10:15:9
10K+15k+9k=102
k=3
b=45
EXPLANATION:
let us assume a,b,c are three numbers
a :b =2:3
b :c =5:3
here in order to make make a:b:c in both ratios b has separate values so multiply by 5 to a:b and 3 by b:c
therefore 5x2:5x3 =10:15
5x3:3x3 =15:9
a:b, b:c is written as a:b:c =>10:15:9
so numbers are in the ratio a:b:c these are not actual values so assume that all of them as a common factor as k
now the numbers are
ak,bk,ck
ak+bk+ck=102
k=102/(a+b+c)
k102/( 10+15+9)
k=102/34
k=3
second number= 15 x 3= 45 - 4 years agoHelpfull: Yes(0) No(0)
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