Answer:
8,100
Step-by-step explanation:
7,200 - 6,400 = 800 increased in 50. Years
What percentage is 800 of 6,400 (%/100 = is/of)
x/100 = 800/6400 (cross multiply)
(800*100)/6400 = 12.50%
(12.50 * 7200)/100 = 900 increased
7,200 + 900 = 8,100
21
You do the parentheses first, so 27/9 = 3
10-3 = 7
3 * 7 = 21
