Jonathan collects postcards and stamps. The number of postcards in his collection is 12 more than 3/4 the number of stamps. He has 39 postcards in all. If Jonathan has x stamps, which equation represents this situation and how many stamps does he have?
12 + (3/4x) = 39
3/4x = 39 - 12
(4/3)(3/4)x = 27 (4/3)
x = 36
He has 36 stamps.
Hope this helps!
For this case we define the following variable:
We now write the equation that models the problem:
\(\frac {3} {4} x + 12 = 39\)
From here, we clear the value of x.
We have then:
\(\frac {3} {4} x = 39-12\\\frac {3} {4} x = 27\\x = (\frac {4} {3}) (27)\\x = (4) (9)\\x = 36\)
Answer:
The number of stamps he has is:
\(x = 36\)