Question 998734
If Sarah is 2times as old as her brother, then 2*brother = Sarah
S= 2b We are going to use this value for Sarah
S-b= 15 In this formula, plug in the value above for Sarah:
2b-b= 15
b= 15 And Sarah, the problem says, is twice as old:
15*2= 30 Sarah is 30. And the problem says Sarah is 15 yrs older:
30-15= 15 We have the correct answer.