Answer:
B. 72
Step-by-step explanation:
The rule of 72 is used as a rough estimate of the number of years required for an investment to double.
According to this rule, the number of years 'n' necessary to double an investment at an annual rate 'r' is:

Therefore, the number that when divided by the interest rate gives the number of years required to double an investment is 72.
The answer is B. 72.
ANSWER:
n = 1.05n divided by 105 times 100
OR
n = (the number of students at the END of the school year) divided by 105 times 100
WORKING OUT:
1.05n = 651 students
1n = 651/105 times 100 = ANSWER
Answer:
the answer is
Step-by-step explanation:
x=1/2y+5---i
4x+3y=-20 ----ii
putting value of x in eqn Ii
4×(1/2×y+5)+3y=-20
2y+5+3y=-20
5y+5=-20
5y=-20-5
5y=-25
y=-25/5
y=-5
putting value in eqn I
x=1/2×-5+5
x=-5/2+5
x=5/2
Answer:
10 is B
11 is D
Step-by-step explanation: