Answer:
In 3 years Mary will be twice John's age. Let's take Mary's present age as 'x'. Therefore , Mary's age in in 3 years = 30. Therefore , Mary's present age is 27.
Step-by-step explanation:
John’s current age = J
J = 12
Mary’s future age = M
Mary’s current age = m
J + 3 = 15
J + 3 = 1/2M
Substitute 12 for J:
12 + 3 = 1/2(m)
15 = 1/2M
Multiply both sides by 2:
30 = M
Mary will be 30 years old in three years, but how old is she now?
M - 3 = m
m = 27
mark me as brainliest:)
