John sold 89 more cheese cookies than blueberry cookies on Monday. On Tuesday, the number of blueberry cookies he sold decreased by 70% while the number of cheese cookies he sold remained the same. He sold each tart for $2.50. He sold a total of 219 cookies on Tuesday. How much money did he receive from the sale of cookies on both days?

	Cheese cookies	Blueberry cookies	Total
Comparing cheese and blueberry cookies  at first	89 more
Before	10 u + 89	10 u	20 u + 89
Change		- 7 u
After	10 u + 89	3 u	13 u + 89

70% = ⁷⁰₁₀₀ = ⁷₁₀

Total number of cookies sold on Tuesday
= 10 u + 89 + 3 u
= 13 u + 89

13 u + 89 = 219
13 u = 219 - 89
13 u = 130 

1 u = 130 ÷ 13 = 10

Total number of cookies sold on Monday
= 10 u + 89 + 10 u
= 20 u + 89

Total number of cookies sold on both days
= 13 u + 89 + 20 u + 89
= 33 u + 178
= 33 x 10 + 178
= 330 + 178
= 508

Total amount received from the sale of cookies on both days
= 508 x 2.50
= $1270

Answer(s): $1270