Answer:
Shorter piece length is 18 inches
Step-by-step explanation:
Let's marked first piece with x and second with y
x + y = 42
Given ratio is x : y = 3 : 4
From this proportion we get
x = 3 c and y = 4 c where c is coefficient of proportionality
when we replace this in initial equation we get
3 c + 4 c = 42 => 7 c = 42 => c = 42/7 = 6 c = 6
x = 3 · 6 = 18 inches and z = 4 · 6 = 24 inches
shorter piece is x = 18 inches
God with you!!!
To solve for proportion we make use of the z statistic.
The procedure is to solve for the value of the z score and then locate for the
proportion using the standard distribution tables. The formula for z score is:
z = (X – μ) / σ
where X is the sample value, μ is the mean value and σ is
the standard deviation
when X = 70
z1 = (70 – 100) / 15 = -2
Using the standard distribution tables, proportion is P1
= 0.0228
when X = 130
z2 = (130 – 100) /15 = 2
Using the standard distribution tables, proportion is P2
= 0.9772
Therefore the proportion between X of 70 and 130 is:
P (70<X<130) = P2 – P1
P (70<X<130) = 0.9772 - 0.0228
P (70<X<130) = 0.9544
Therefore 0.9544 or 95.44% of the test takers scored
between 70 and 130.
At the same rate, 31 inches of wire will cost 124 cents.
The correct answer is option D
The solution is shown below:
