To find the cost of each book, you need to divide the money spent on all of the books by the number of books.
$39 / 10 = $3.90 per book
Answer: common difference = -5
Step-by-step explanation:
This is an arithmetic progression. The common difference will be gotten by subtracting the 1st term from the 2nd term. This will be:
1st term = 12
2nd term = 7
3rd term = 2
Common difference = 7 - 12 or 2 - 7 = -5
It isn't an geometric progression as the ratio isn't thesame
= 2nd term / 1st term
= 7/12
= 3rd term / 2nd term
= 2/7
Therefore, it's an arithmetic progression with difference of -5
400 ÷ 77 x 100 + 2000 - 55 + 999
u would use dmas :
1. division
2. multiplication
3. addition
4. subtraction
400 ÷ 77 = 5.19
5.19 x 100 + 2000 - 55 + 999
5.19 x 100 = 519
519 + 2000 - 55 + 999
519 + 2000 + 999 = 3518
3518 -55 = 3463
hope this helps