Erin and jamie are collecting shells while the tide is out. erin has 27 shells, and she has 9 more than jamie. write and equation for this situation and find how many shells jamie has collected. a. 27 = j + 9; jamie collected 18 shells b. 27 = j – 9; jamie collected 36 shells c. 27 + 9 = j; jamie collected 36 shells d. 27 = j + 9; jamie collected 36 shells

A.

Erin's total minus 9 gives us Jamie's total. This means Erin's total equals Jamie's total plus 9. This leads us to the conclusion that 27 (E's total) = j + 9 (the difference). We also know from the first phrase that E - 9 = j, meaning 27 - 9 = j, so j = 18.

n=9

step-by-step explanation:

7 times a number = 7n

decreased by 13 = 7n-13

same as is =

5 times the number = 5n

increased by 5 = 5n+5

7n-13 = 5n+5

2n=18

n=9

the arc length is found by finding the circumference of the full circle (2xpixradius) and then dividing by 4 to find just one quarter of the circle (90 degrees).