Answer:
Step-by-step explanation:
1)
2(x – 4) + 32
Multiply it out.
2 * x - 2 * 4 + 32
2x - 8 + 32
2x + 24
2)
9x + 4(x + 2) – 5
Multiply it out
9x + 4 * x + 4 * 2 - 5
9x + 4x + 8 - 5
13x + 3
Answer:
x=3
Step-by-step explanation:
If k is between J and L, then
JK + KL = JL
2x+11 + (3x) = 13x-13
Combine like terms
5x +11 = 13x -13
Subtract 5x from each side
5x-5x+11 = 13x-5x-13
11 = 8x-13
Add 13 to each side
11+13 = 8x-13+13
24 = 8x
Divide by 8
24/8 = 8x/8
3 =x
Answer:
8a + 24
Step-by-step explanation:
Use Distributive property: a(b +c) = a*b + a*c
Here a = 8 ; b= a & c = 3
8(a + 3) = 8*a + 8*3
= 8a + 24
Answer:
a) 229 and 305 days
b) 229 days or less
c) 305 days or more
Step-by-step explanation:
The Empirical Rule(68-95-99.7 rule) states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 267
Standard deviation = 19
(a) Between what values do the lengths of the middle 95% of all pregnancies fall?_____________and___________days
By the Empirical rule, 95% of all pregnancies fall within 2 standard deviations of the mean.
So
267 - 2*19 = 229 days
to
267 + 2*19 = 305 days
(b) How short are the shortest 2.5% of all pregnancies?______days or less
95% of all pregnancies fall within 2 standard deviations of the mean. The other 5% are more than 2 standard deviations from the mean. Since the distribution is symmetric, 2.5% is more than 2 standard deviations below the mean(shortest 2.5%) and 2.5% is more than 2 standard deviations above the mean(longest 2.5%). So
267 - 2*19 = 229 days
c) How long do the longest 2.5% of pregnancies last?________days or more
Explanation in b)
267 + 2*19 = 305 days
Ummm, we can't choose one of the problems if we can't see any of the problems...
