Weekly wages at a certain factory are normally distributed with a mean of $400 and a standard deviation of 50. find the probability that a worker selected at random makes between $300 and $400

47.5%

Step-by-step explanation:

Find the z-scores:

z = (x − μ) / σ

z₁ = (300 − 400) / 50 = -2

z₂ = (400 − 400) / 50 = 0

300 is 2 standard deviations below the mean, and 400 is 0 standard deviations from the mean.

From the empirical rule, 95% of a normal distribution is between -2 and +2 standard deviations.  Since normal distributions are symmetrical, that means half of that is between -2 and 0 standard deviations.

95% / 2 = 47.5%

b. an equilateral triangle inscribed in a circle

step-by-step explanation:

we are given the figure of two circles having a triangle inside.

now, we know that,

"when a figure is lying inside an another figure, then the outside figure is known as circumscribed figure and the figure lying inside is referred to as the inscribed figure".

as we see that, the circles are containing the triangle completely.

thus, the circles are the circumscribed figures and the triangle is the inscribed figure.

hence, we get, 'an equilateral triangle is inscribed in a circle'.

i got 10.28 but that rounds up to 10.3