ratio and proportion solution10

Ratio and Proportion Solution10

In this page ratio and proportion solution10 we are going to see solution of each question from the worksheet ratio and proportion.

(15) If a : b = 3 : 2 and b : c = 5 : 8,find a: c and a : b : c .

Solution:

a : b =3 : 2

a/b = 3/2

b : c = 5/8

b/c = 5/8

we can write a : c as (a/c) => (a/b) x (b/c) = (3/2) x (5/8)

(a/c) = (15/16)

a : c = 15 : 16

a : b =3 : 2

= 1 : (2/3)

Now we have to multiply by 15,

= 1(15) : (2/3) (15) : 16 (15)

= 15 : 10 : 240

We can simplify this by 5,so we get

a : b : c = 3 : 2 : 48

(16) If x : y = 5 : 7 and y : z = 4 : 5, find x : z and x : y : z

Solution:

x : y = 5 : 7

x/y = 5/7

y : z = 4 : 5

y/z = 4/5

we can write x : z as (x/z) => (x/y) x (y/z) = (5/7) x (4/5)

(x/z) = (4/7)

x : z = 4 : 7

y : z = 4 : 5

= 1 : (5/4)

Now we are going to multiply it by 4, so we get

= 4 : (5/4) x 4

= 4 : 5

x : y : z = 4 : 4 : 5

(17) If x : y = 2 : 1 find (5 x + 8y) : (6 x – 7y)

Solution:

x : y = 2 : 1

x/y = 2/1

(5 x + 8y) : (6 x – 7y) = (5 x + 8 y) /(6 x – 7 y)

Divide both numerator and denominator by x, so we get

= [5 + 8(x/y)]/[6 – 7(x/y)]

= [5 + 8(2/1)]/[6 – 7(2/1)]

= [5 + 16]/[6 – 14]

= 21/[– 8]

= -21/8

Therefore the value of (5 x + 8y) : (6 x – 7y)is -21/8

ratio and proportion solution10 ratio and proportion solution10