Susan was 20 years old when her daughter 'janet' was born .what will Janet's age be when the ratio is 7:2
To find out Janet's age when the ratio is 7:2, we need to know the current age of Janet. Could you please provide Janet's current age?
To find out Janet's age when the ratio is 7:2, we need to determine the age difference between Susan and Janet.
Since Janet was born when Susan was 20 years old, the age difference between them is always 20 years.
Next, we need to calculate the multiple of the ratio that represents the age difference between them.
The given ratio is 7:2, which means there are a total of 9 parts (7+2).
To calculate the age difference between Susan and Janet, we divide 20 (the difference in their ages) by 9 (the total number of parts in the ratio).
Age difference per part = 20/9
Now, we can determine Janet's age when the ratio is 7:2.
Janet's age = Susan's age + (Age difference per part * Multiple of the ratio)
For example, if the multiple of the ratio is 5, Janet's age would be:
Janet's age = 20 + (20/9 * 5)
Now, you can calculate Janet's age by substituting the desired multiple of the ratio into the equation.
S / (S - 20) = 7 / 2 ... 2 S = 7 S - 140
solve for S , then subtract 20 to find Janet's age