They are right except for 12. i think it is C but i could be wrong.
Answer:
The word "Of" in an equation is interpreted to be multiplication. Also, you must move the decimal two places to the left to change a percent to a decimal.
1. 20 * .12 = 2.4
2. .3 * 70 = 21
3. 300 * .25 = 75 Blue marbles
4. 40 * .35 = $14
5x = 4y - 3
Standard form is Ax + By = C, so first subtract 4y to both sides:
5x - 4y = -3
