Answer :
Ann and Bob's age is 21 years and 28 years respectively and after 14 years the ratio will be 5:6.
What is Ratio ?
The comparison of one quantity to other is called a ratio and when two ratios are equal they are said to be in proportion.
It is given in the question that
The ratio of Ann's age to bob's age is 3:4
in 7 years time this ratio will be 4:5
their ages now = ?
Let the age of Ann and Bob is x and y
x:y = 3:4
x =(3/4)y
After seven years
(x+7):(y+7) = 4 :5
(x+7)/(y+7) = 4/5
((3/4)y +7)/(y+7) = 4/5
(3y +28)/(y+7) = 16/5
5*(3y+28)= 16(y+7)
15y +140 = 16y+112
y = 140-112
y =28 years
x = 21 years.
After x years suppose the ratio is 5 :6
(21+x)/(28+x) = 5:6
126 +6x = 140 + 5x
x = 14 years.
Therefore after 14 years the ratio will be 5:6.
To know more about Ratio
https://brainly.com/question/13419413
#SPJ1