The 68-95-99.7 rule tells us 68% of the probability is between -1 standard deviation and +1 standard deviation from the mean. So we expect 75% corresponds to slightly more than 1 standard deviation.
Usually the unit normal tables don't report the area between -σ and σ but instead a cumulative probability, the area between -∞ and σ. 75% corresponds to 37.5% in each half so a cumulative probability of 50%+37.5%=87.5%. We look that up in the normal table and get σ=1.15.
So we expect 75% of normally distributed data to fall within μ-1.15σ and μ+1.15σ
That's 288.6 - 1.15(21.2) to 288.6 + 1.15(21.2)
Answer: 264.22 to 312.98
Answer:
A8 = 66 [8th term]
Step-by-step explanation:
Given the explicit arithmetic sequence An = -14 + 10n → -4 + 10(n-1)
To find the 8th term. An nth term is where n is n in the sequence. So substitute 8 for n, and simplify.
So A8 = -4 + 10(8-1) → -4 + 10(7) → -4 + 70 → 70 - 4 → 66.
Answer:
its letter A
Step-by-step explanation:
Step-by-step explanation:
step 1: how many dolphins
there are 6 sharks
sharks to dolphins is 3 to 5
3 S to 5 D
we can divide 6 (amount of sharks known) by 3, to get what a ratio of 1 is
6 ÷ 3 = 2
so 2 sharks is = 1 part or ratio
now we can times by 5 to get a ratio of 5
5 × 2 = 10
there are 10 Dolphins
Step 2: How many starfish
repeat the steps above but for the ratio 2: 7 where 2 is the Dolfin ratio and there are 10 dolphins
put in questions answer you got
Answer:
x = 61
Step-by-step explanation:
The angle above the line n adjacent to 2x - 6 is (x + 3) alternate angle.
Adjacent angles are supplementary, thus
2x - 6 + x + 3 = 180, that is
3x - 3 = 180 ( add 3 to both sides )
3x = 183 ( divide both sides by 3 )
x = 61