Answer:
A i. a:c=3:10
ii. a:b:c=2:5:10
B i. x:z=2:5
ii. x:y:z=2:4:5
Step-by-step explanation:
A.) If a:b = 2:5 and b:c = 3:4, find (i) a:c(ii) a:b:c
a:b=a/b=2/5
b:c=b/c=3/4
a/b*b/c=a/c
2/5*3/4=a/c
6/20=a/c
3/10=a/c
Therefore, a:c=3:10
a:b:c
a:b=2:5
b:c=3:4
b is common to both ratios
The value of b in the first ratio is 5 and b is 3 in the second ratio
Lets take the LCM of both values
LCM of 5 and 3=15
So, we will change the value of b in the first ratio and second ratio to 15
By doing this, we will multiply the whole first ratio by 3
We have, 6:15
We multiply the whole second ratio by 5
We have, 15:20
Therefore a:b:c=6:15:20
=2:5:10
B. If x:y = 1:2 and y:z = 4:5,
x:y=x/y=1:2
y:z=y/z=4:5
x/y*y/z=x/z
1/2*4/5=x/z
4/10=x/z
2/5=x/z
Therefore, x:z=2:5
x:y:z
x:y=1:2
y:z=4:5
y is common to both ratio
Take the LCM of y values in both ratio
LCM of 2 and 4 =4
So,we will change the value of y in the first and second ratio to 4
By doing this, we will multiply the whole first ratio by 2
We have, 2:4
We will also multiply the whole second ratio by 1
We have, 4:5
Therefore, x:y:z=2:4:5
