Answer:
It is 102
Step-by-step explanation:
Answer:
Step-by-step explanation:
1) phone
38.95 = 0.03 * mins + 29.95
9.00 = 0.03 * mins
9.00 /0.03 = mins
300 = mins
so he used 300 minutes :)
2) books
8.70 =14 * bookPrice + 2.40
6.30 = 14 * bookPrice
6.30 / 14 = bookPrice
0.45 = bookPrice
each book cost 45 cents :)
Remark
You can find the answer to that by dividing any 2 consecutive terms putting the right one in the numerator and the left one in the denominator.
Forumula
ratio = right/left
right = - 8
left = 4
ratio = -8/4
ratio = -2
Any two numbers would work.
ratio = - 32/16 = - 2
2.75 is 110%
2.75/1.1=2.50
Therefore, the main bill was two and a half dollars