If
b
a
=
9
7
and
c
b
=
5
3
, then the value of a:b:c is:
- A7 : 3 : 15
- B21 : 27 : 42
- C7 : 9 : 15
- D7 : 9 : 5
Solution & Step-by-step Explanation
We are given two ratios:
a:b=7:9
b:c=3:5
To combine them, we need to make the value of the common term b equal in both ratios. The current values of b are 9 and 3. The LCM of 9 and 3 is 9.
Multiply the second ratio by 3:
b:c=(3×3):(5×3)=9:15
Now that b is equal in both ratios (b=9):
a:b:c=7:9:15
a:b=7:9
b:c=3:5
To combine them, we need to make the value of the common term b equal in both ratios. The current values of b are 9 and 3. The LCM of 9 and 3 is 9.
Multiply the second ratio by 3:
b:c=(3×3):(5×3)=9:15
Now that b is equal in both ratios (b=9):
a:b:c=7:9:15