Answer:
t ≤ 15
Step-by-step explanation:
Let t = tables
6 * 15 + 2* t ≤ 120
90 + 2t ≤ 120
2t ≤ 30
t ≤ 15
Given:
The equation is

To find:
The reason for second step.
Solution:
We have,

Using multiplication property of equality, multiply both sides by 3.

Using addition property of equality, add 4 on both sides.


Using division property of equality, divide both sides by 2.


So, the reason for second step is multiplication property (=).
Therefore, the correct option is D.
Answer:
We have a normal distribution with a mean of 267 days and a standard deviation of 15 days. To solve this proble we're going to need the help of a calculator.
a. The probability of a pregnancy lasting 309 days or longer is:
P(z>309) = 0.0026 or 0.26%
b. The lowest 4% is separeted by the 240.74 days. The probability of pregnancy lasting 240.74 days is 4%.
4b + 10 = 42
b = 8
32 + 10 = 42