I gotchu the answer is -8.6
You need to apply the same reasoning.
25 cents is 25% of a dollar because they are 25 out of 100, that is 25/100 = 25%
For 23 cents is exactly the same reasoning:
23 cents is 23% of a dollar <span>because they are 23 out of 100 cents, that is 23/100 = 23%</span>
84 blue marbles.
Steps:
1) Use the 3:7 ratio
2) Since there are 36 red marbles, you should know to multiply the ratio by 12.
3) Multiply 7 by 12 (7x12=84)
