In an all boys school, the heights of the student body are normally distributed with a mean of 69 inches and a standard deviation of 3 inches. Using the empirical rule, determine the interval of heights that represents the middle 95% of male heights from this school.

Two intervals are 63 and 75

Step-by-step explanation:

Given:

Mean of students (μ) = 69 inches

Standard deviation (σ) = 3 inches μ

Find:

Interval of heights (95%) using empirical rule

Computation:

Interval of heights (95%) using empirical rule:

⇒ μ – 2σ = 69 - 2(3)

⇒ μ – 2σ = 69 - 6

⇒ μ – 2σ = 63

⇒ μ + 2σ = 69 + 2 (3)

⇒ μ + 2σ = 69 + 6

⇒ μ + 2σ =  75

Two intervals are 63 and 75

s

step-by-step explanation:

x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x

step-by-step explanation:

last month maria hiked the 5-mile mountain trail a number of times and she hiked the 10-mile canal trail several times. let x represent the number of times she hiked the 5-mile trail, and let y represent the number of times she hiked the 10-mile trail. if she hiked a total of 90 miles, which equation can be used to find the number of times maria hiked each trail? x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x