Answer:
a) 2.0702
b) 2.07
Step-by-step explanation:
Given:
Sample, n = 840
standard deviation, σ = 60
a) The standard deviation of the sampling distribution, will be:
= 2.0702
Standard deviation of the sampling distribution is 2.0702
b) According to the 68 part of the 68-95-99.7 rule, 68% of all values of x fall within 1 standard deviation on either side of the unknown mean μ.
Therefore, missing number will be:
= 1 * 2.0702
= 2.0702 ≈ 2.07
Answer:
Commutative property of addition of rational numbers: Two rational numbers can be added in any order. Thus for any two rational numbers a/b and c/d, we have. (a/b + c/d) = (c/d + a/b)

Explanation:
Since we have given that
Speed at which Eugene walked all the way to school = 3 mph
After realizing that she forgot her math book, she ran back
Speed at which Eugene walked back to her house = 7 mph
Let the distance between her house and her school be x
According to question,

Hence,
