Donald is 38 years younger than Natalie. 5 years ago, Natalie's age was 3 times Donald's age. How old is Donald now?

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  24

Step-by-step explanation:

Let d represent Donald's age now. Then Natali's age now is d+38. The age relationship 5 years ago was ...

  (d+38) -5 = 3(d -5)

  d +33 = 3d -15 . . . . . eliminate parentheses

  48 = 2d . . . . . . . . . . . add 15-d

  24 = d . . . . . . . . . . . . . divide by 2

Donald is 24 years old now.

Alternate solution

You can also work this by considering that 5 years ago, Natalie's age was more than Donald's age by twice Donald's age then. Hence Donald was 38/2 = 19 at that time. Now, Donald is 19+5 = 24.

look at the picture.

1.

ef : ab = 2 : 3

gf : cb = 2 : 3

gh : cd = 2 : 3

he : da = 2 : 3

2.

∠a ≅ ∠e

∠b ≅ ∠f

∠c ≅ ∠g

∠d ≅ ∠h

3.

use pythagorean theorem:

the length of the abcd trapezoid sides:

|ab| = 3 cm

|bc| = 10 cm

|cd| = 3(3) cm = 9 cm

|da| = 8 cm

the perimeter of abcd = 3 + 10 + 9 + 8 = 30 cm

the ratio of perimeters of the tarapezoids is equal 2 : 3.

substitute:

      cross multiply

      divide both sides by 3