The "rule of 72" says that the doubling time in years is approximately 72 divided by the interest rate in percent. To make the money grow by a factor of 4 requires that it double twice, so will take twice as long as the period to double once.
2×72/11.3 ≈ 12.7 . . . . years
_____
The "rule of 72" is an approximation. The actual quadrupling time for this interest rate and compounding is about 12.6 years. (The actual product of doubling time and nominal interest rate is about 71.25.)
Answer:
The sum of half of a number and three-fourths is at least five and one quarter
Step-by-step explanation:
It's all about making sense of an English sentence.
"half the sum ..." is different from "the sum of half ..."
And ...
"at least" and "not less than" mean the same (≥)
"not more than" and "at most" mean the same (≤)
_____
Since all of the expressions are written out in words, it is a matter of matching the ideas expressed. That's a problem in reading comprehension, not math.
__
"One-half x + three-fourths [is] greater-than-or-equal-to 5 and one-fourth"
means the same as ...
"The sum of half of a number and three-fourths is at least five and one quarter"
Answer:
Option E: 24.
Step-by-step explanation:
When Caleb (C) has 20 more books than Danica (D), we have:
(1)
Now, when Caleb gives Danica half of his books:
(2)
Danica will have 4 more books than Caleb, so:
(3)
Also we have that:
(4)
By entering equation (2) and equation (3) into equation (4) we have:
(5)
From (1) we have:
(6)
By entering (6) into (5):


And, from (6):
Therefore, the correct option is E, Caleb had to start with 24 books.
I hope it helps you!
The answer is (-x^2 - 3x +28)
Answer:
I think is is a bit b
Step-by-step explanation:
a or b