X<4 hope this helped dude
Answer:
last set of numbers will be<em><u> 1 9 2 0</u></em>
Answer: 3:8
Explanation: To get this you have to divide each number by the two numbers' GCF (Greatest Common Factor) and in this case the GCF is 10, so you divide both numbers by 10 and get 3 and 8.
1. 72 to 50 points
50/72 = 69%
100-69= 31% decrease
2. 14 to 40 books
14 / 40 = 35%
100-35= 65% increase
3. 10 plus 30% increase
10 * 0.3 = 13