Answer:
C. 12
Step-by-step explanation:
With the rule of 72, you would divide 72 by the periodic interest rate to get the number of years for the principal to double
72 ÷ 6 = 12
Answer:

Step-by-step explanation:

+18



All are equal except A/D = C/B
I replaced the values with numbers
a=5 b=10 c=50 d=100
10/5=100/50 so it’s not b/a = d/c
5/10=50/100 so it’s not a/b = c/d
5/50 = 10/100 so it’s not a/c = b/d
5/100 is NOT 50/10 so it’s NOT a/d = c/b
#3 answer: 42
3x7= 21
21x2=42
#4 answer:140
5x7=35
2x2=4
4x35=140