Step-by-step explanation:
step 1. 17/21 - 2/10 = x (in order to subtract you need a common denominator)
step 2. (17/21)(10/10) - (2/10)(21/21) = x
step 3. 170/210 - 42/210 = x
step 4. 128/210 = 64/105 = x
step 5. x = 64/105.
Answer:
95% Confidence interval = (23.4,26.2)
Step-by-step explanation:
In this problem we have to develop a 95% CI for the mean.
The sample size is n=49, the mean of the sample is M=24.8 and the standard deviation of the population is σ=5.
We know that for a 95% CI, the z-value is 1.96.
The CI is
![M-z*\sigma/\sqrt{n}\leq\mu\leq M+z*\sigma/\sqrt{n}\\\\24.8-1.96*5/\sqrt{49}\leq\mu\leq 24.8+1.96*5/\sqrt{49}\\\\ 24.8-1.4\leq\mu\leq 24.8+1.4\\\\23.4\leq\mu\leq 26.2](https://tex.z-dn.net/?f=M-z%2A%5Csigma%2F%5Csqrt%7Bn%7D%5Cleq%5Cmu%5Cleq%20M%2Bz%2A%5Csigma%2F%5Csqrt%7Bn%7D%5C%5C%5C%5C24.8-1.96%2A5%2F%5Csqrt%7B49%7D%5Cleq%5Cmu%5Cleq%2024.8%2B1.96%2A5%2F%5Csqrt%7B49%7D%5C%5C%5C%5C%2024.8-1.4%5Cleq%5Cmu%5Cleq%2024.8%2B1.4%5C%5C%5C%5C23.4%5Cleq%5Cmu%5Cleq%2026.2)
Answer:
81
Step-by-step explanation:
9 x 9 = 81
So, 81 is the perfect square.
Idk you kno I am trying to get points right