Answer :
You have to plug in the numbers.
So first let's plug in 13. 7*13+8=99
Now 15. 7*15+8=113
Now 18. 7*18+8=134
Lastly 20. 7*20+8=148
The answer is 13.
So first let's plug in 13. 7*13+8=99
Now 15. 7*15+8=113
Now 18. 7*18+8=134
Lastly 20. 7*20+8=148
The answer is 13.
You have $100 but the shipping is $8 so you subtract that from $100 and get $92, At $7 dollers a book you can get 13 books before going over 7x13=91. So the answer is 13 and you will spend $99 total.