HELP WITH MATHS URGENT?

2017-04-12 1:08 pm
A man is 37 years old and his daughter is 5 years old. In how many years time will the man be 3 times the age of his daughter?

回答 (5)

2017-04-12 1:16 pm
Let y years be the time needed that the age of the man will be 3 times that of his daughter.

In y years time, the man will be (37 + y) years old, and his daughter will be (5 + y) years old.
37 + y = 3(5 + y)
37 + y = 15 + 3y
2y = 22
y = 11

Time needed = 11 years
2017-04-12 1:34 pm
(m - d)/2 - d = (m - 3d)/2 = (37-15)/2 = 22/2 = 11

In 11 years the daughter will be 16, and her father 48 = 16 × 3.
2017-04-12 9:31 pm
Well,

Let's suppose that will be the case in n years
then n verifies :
37 + n = 3( 5 + n)
3(n + 5) = 37 + n
3n + 15 = 37 + n
3n - n + 15 = 37 + n - n
2n + 15 = 37 + 0
2n + 15 - 15 = 37 - 15
2n + 0 = 22
1/2 * 2 * n = 22/2
1 * n = 11
n = 11

Answer : in 11 years

hope it' ll help !!
2017-04-12 2:58 pm
37 + x = 3 [ 5 + x ]
37 + x = 15 + 3x
22 = 2x
x = 11
In 11 years.
2017-04-12 1:11 pm
Hint:
x=number of years


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