Let's call Maura's age now M and Cara's age now C.
We know Maura is five years younger than Cara. In symbols that is, M - 5 = C
We also know that 7 years ago Maura's age was half of Cara's. Maura's age 7 years ago was M-7 and Cara's age seven years ago was C-7. Since Maura's age (7 years ago) was half of Cara's we can write in symbols:
Let's take that last equation and substitute C - 5 for M (this is because according to our first equation these are equal). When we do this we get an equation with only C as the variable and solve for C as follows:
Cara is 17. Since Maura is 5 years younger she is 12.
As a check, seven years ago Cara was 10 and Maura was 5. It is the case that Maura was half Cara's age seven years ago.
So it is really easy to solve firstly we can see how much does the first 10 boxes make which makes around 55$ obviously. Secondly 45$ for the next 10 boxes.
So for now we can simply calculate that we have spent around 100$ which means 20 boxes. The remaining money left is 77$ so we can buy 77/3.5 = 22 only 22 boxes with that money. Hence a total of 42 boxes.
Answer:
An irrational number has a repeating decimal digits that continues on infinitely
Step-by-step explanation: