Answer: The proportion that will qualify is 0.0314 or 3.14%.
First, we need to find the z-score of a time of 128 seconds. To do this, we find the difference of the mean and score and divide by the standard deviation.
(128 - 141) / 7 = -1.86
Now, use a standard normal distribution table to determine the percent below a z-score of -1.86. That value is 0.0314 or 3.14%.
Answer:
x intercept is (0.9,0)
y intercept is (0,-1.2)
Step-by-step explanation:
Answer:
x=-6
Step-by-step explanation:
Answer:
The ages of the four siblings are: 5, 7, 9 and 11 years old.
Step-by-step explanation:
The computation of the age of the four siblings is shown below:
Given that
n = 4
a1 =? a2 =? a3 =? a4 =?
a4 = a1 + 6 years
S4 = 32
Based on the above information
As we know that
Sn = (a1 + a4) × n ÷ 2
S4 = (a1 + a4) × 4 ÷ 2
32 = (a1 + a1 +6) × 2
16 = 2a1 + 6
2a1 = 10
a1 = 10 ÷ 2
= 5
So, a4 = a1 +6
= 5 +6
= 11
a4 = a1 + (4-1) × d
11 = 5 + 3 × d
d = 6 ÷ 3
= 2
So,
a2 = a1 + d
= 5 + 2
= 7
a3 = a2 + d
= 7 + 2
= 9
Hence, The ages of the four siblings are: 5, 7, 9 and 11 years old.
Answer: x=3.4
Step-by-step explanation:
0.5x + 4.2 = 5.9 \\ 0.5x = 5.9 - 4.2 \\ 0.5x = 1.7 \\ x = 1.7 \div 0.5 \\
