Answer:
(b) The probability is 0.375
(c) The probability is 0.750
Step-by-step explanation:
The probability is calculated as a division between the number of options that satisfy a condition and the total number of options.
For part (b), we have 8 cavities or options for obtain the part but we want to obtain the part from cavity 1, 2 or 3, so we have 3 options. Therefore, the probability is:

For part (c), We have 8 cavities or options for obtain the part and we want to obtain the part from any cavity except cavity 3 or 4, so we have 6 options. These options are cavity 1, cavity 2, cavity 5, cavity 6, cavity 7 and cavity 8. Then, the probability is:

The area of the rectangle is length times width, that is
A = L*W
The problem requires the width so
W = A/L
Given that A = 437 sq. cm and L = 19 cm, therefore
W = 437/19 = 23 cm
That is the answer.
A.
Let x = age of Samantha.
Then x - 2 = age of Emily,
and x + 2 = age of Lauren.
b.
x - 2 + x + x + 2 = 42
c.
x - 2 + x + x + 2 = 42
3x = 42
x = 14
x - 2 = 14 - 2 = 12
x + 2 = 14 + 2 = 16
The ages of the sisters are 12, 14, 16.
Answer:
Quinzel sold 17 pairs of shoes last month.
Step-by-step explanation:
Let be "Q" the number of pairs of shoes Quinzel sold last month and "J" the number of pairs of shoes Joseph sold last month.
Set up a system of equations:

Solve for "J" from the first equation:

Applying the Substitution Method, you get:

the number of elements in the union of the A sets is:5(30)−rAwhere r is the number of repeats.Likewise the number of elements in the B sets is:3n−rB
Each element in the union (in S) is repeated 10 times in A, which means if x was the real number of elements in A (not counting repeats) then 9 out of those 10 should be thrown away, or 9x. Likewise on the B side, 8x of those elements should be thrown away. so now we have:150−9x=3n−8x⟺150−x=3n⟺50−x3=n
Now, to figure out what x is, we need to use the fact that the union of a group of sets contains every member of each set. if every element in S is repeated 10 times, that means every element in the union of the A's is repeated 10 times. This means that:150 /10=15is the number of elements in the the A's without repeats counted (same for the Bs as well).So now we have:50−15 /3=n⟺n=45