I always had trouble doing percents, but my last algebra teacher taught me an easy way, where you turn the percent into a decimal.
Maria: to find 25% of 26.50, you multiply 26.50 by 0.25 to get 6.625. now, you subtract 6.625 from 26.50 to get 19.875. which would round to 19.88$. To find the 10% sales tax, you multiply 19.88 by 0.10 or 0.1 to get 1.988. that would round to 2.00. She would then add 19.88 and 2.00 to get 21.88$.
Edwin: I am not even sure how to figure out Edwin's math, his is not even comprehendible for me.
When I'm shopping, I always use Maria's method to figure out the price of things, therefore, I am 99% sure she is correct and Edwin is not. If it said that they both came with 23$, and the price of the book is now only 21.88, then yes, they have enough money to purchase the book.
and sorry this took long, I'm multitasking.
Answer: (total amount paid - $40) / 0.05
Step-by-step explanation:
Given the following :
Monthly fee = $40
Additional fee = $0.05 per minute on phone
Given the the amount paid for the month is available, number of minutes he was on phone can be determined thus :
Total amount to be paid = monthly fee + additional fee
Additional fee = $0.05 × n
Where n = number of minutes on phone
Hence,
Total amount paid = $40 + $0.05n
If the amount paid is known, the number of minutes on phone can be calculated thus;
(Total amount paid - monthly fee) = $0.05n
n = (Total amount paid - monthly fee) / fee per minute on phone
(total amount paid - $40) / 0.05
