During its first week of business, a market sold a total of 108 apples and oranges. The second week, five times the number of apples and three times the number of oranges were sold. A total of 452 apples and oranges were sold during the second week. Determine how many apples and how many oranges were sold the first week.

1 answer

a = apples

o = oranges

1 week :

a + o = 108

2 week :

5 a + 3 o = 452

Now you must solve system of 2 equations with 2 unknown :

a + o = 108

5 a + 3 o = 452

The method of substitution:

a + o = 108 Subtract o to both sides

a + o - o = 108 - o

a = 108 - o

5 a + 3 o = 452

5 * ( 108 - o ) + 3 o = 452

5 * 108 - 5 * o + 3 o = 452

540 - 5 o + 3 o = 452

540 - 2 o = 452 Subtract 540 to both sides

540 - 2 o - 540 = 452 - 540

- 2 o = - 88 Divide both sides by - 2

- 2 o / - 2 = - 88 / - 2

o = 44

a = 108 - o

a = 108 - 44 = 64

64 apples and 44 oranges