X represent the number of laps Marcy swam, 114x represent the number of times Toni swam.

20 + 0.80(114x) + 15 + 0.85x = 257
20 + 91.2x + 15 + 0.85x = 257
92.05x + 35 = 257

Required equation is 92.05x + 35 = 257

3 0

3 years ago

Hiro has a stack of cards with one number from the set 1, 1, 2, 2, 3, 3, 3, 4 written on each card. What is the probability that

professor190 [17]

Answer:

Therefore, the probability is P=3/32.

Step-by-step explanation:

We know that Hiro has a stack of cards with one number from the set 1, 1, 2, 2, 3, 3, 3, 4 written on each card.

We calculate the probability that he pulls out a 3 first and then pulls out a 2 without replacing them.

The probability that he pulls out a 3 first is 3/8.

The probability of a second card being 2 is 2/8.

We get:

$P=\frac{3}{8}\cdot \frac{2}{8}\\\\P=\frac{6}{64}\\\\P=\frac{3}{32}$

Therefore, the probability is P=3/32.

7 0

3 years ago

Triangle X Y Z is shown. The length of side X Y is (9 n + 12) feet and the length of side X Z is (15 n minus 6) feet. Angles X Y

posledela

*the figure is shown in the attachment

Answer/Step-by-step explanation:

Since <XYZ and <YZX are said to be congruent, therefore, the side opposite to each of the angle are also equal. Therefore, ∆XYZ is an isosceles ∆.

Find the value of n by creating an equation to solve for n:

XY = (9n + 12) ft

XZ = (15n - 6) ft

XY = XZ (2 equal lengths of isosceles ∆)

9n + 12 = 15n - 6 (substitution)

Combine like terms

9n - 15n = - 12 - 6

-6n = -18

Divide both sides by -6

-6n/-6 = -18/-6

n = 3

Find the length of leg XY by substituting n = 3 into XY = (9n + 12) ft.

XY = (9(3) + 12) ft

XY = (27 + 12) ft

XY = 39 ft

Find the length of leg XZ by substituting n = 3 into XZ = (15n - 6) ft.

XZ = (15(3) - 6) ft

XZ = (45 - 6) ft

XZ = 39 ft

7 0

3 years ago