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sweet-ann [11.9K]

3 years ago

12

A textbook store sold a combined total of 294 history and sociology textbooks in a week. The number of history textbooks sold wa

s 86 more than the number
of sociology textbooks sold. How many textbooks of each type were sold?

1 answer:

lorasvet [3.4K]3 years ago

8 0

Answer:

8

Step-by-step explanation:

You might be interested in

Santos went on a bike ride of 90 miles. He realized that if he had gone 24 mph faster, he would have

Gnoma [55]

<h3>Answer: 6 mph</h3>

========================================

Explanation:

distance = rate*time

90 = r*t

where r is the slower speed and t is the time it takes when going that slower speed.

If r is bumped up 24 mph faster, to r+24, then Santos takes t-12 hours to get there. The second equation is

90 = (r+24)(t-12)

-------------------------------------

We can solve the first equation for r to get r = 90/t

Then plug this into the second equation and do a bit of algebra

90 = (r+24)(t-12)

90 = (90/t+24)*(t-12)

90 = 90 - 1080/t + 24t - 288

90t = 90t - 1080 + 24t^2 - 288t

0 = 90t - 1080 + 24t^2 - 288t-90t

0 = 24t^2 - 288t - 1080

24t^2 - 288t - 1080 = 0

If you apply the quadratic formula, then you should get the two solutions t = -3 and t = 15. Due to time constraints, I'll skip these steps.

We'll ignore the negative t value. It makes no sense to have a negative time.

So we focus on t = 15 as the only solution.

-------------------------------------

If t = 15, then,

r = 90/t

r = 90/15

r = 6

Santos rode his bike at <u>6 mph</u> at first. Going this speed means he takes 15 hours.

If he rode 24 mph faster, at 6+24 = 30 mph, then he would ride for 15-12 = 3 hours instead. Note that 90/30 = 3.

5 0

3 years ago

Helllpppp meeeee plsssssss

Ainat [17]

Answer:

The inequality $\frac{8}{4}\:$ is true.

Step-by-step explanation:

Given

$\frac{8}{5}$

FALSE

Reason: 8/5 or 1.6 is greater than 9/10 or 0.9

$1>\frac{6}{5}$

FALSE

Reason: 1 is smaller than 6/5 or (1.1)

$\frac{5}{2}$

converting mixed number to improper fraction

$\frac{5}{2}$

FALSE

Reason: 5/2 can not be less than 5/2

$\frac{8}{4}\:$

$2$

TRUE

Reason: 2 is indeed smaller than 5/2 or 5.2 ∵ 5/2 = 2.5

Therefore, inequality $\frac{8}{4}\:$ is true.

7 0

3 years ago

If 1cm represents 5m, what would be an area of 6 square cm. represent?

Vlad1618 [11]

Answer:

150 m²

Step-by-step explanation:

Given 1 cm represents 5 m

⟹1 cm=5 m

given area =6 cm² =6×(5 m)² =6×25 m²

=150 m²

area of 6 cm² represents 150 m²

7 0

3 years ago

Explain how to find 4 times 754 using two different methods

Nina [5.8K]

1. 4x754=5278
2. you could use exponets

6 0

3 years ago

Read 2 more answers

Dorothy Little purchased a mailing list of 2,000 names and addresses for her mail order business, but after scanning the list sh

amm1812

Answer: c. 0.0778

Step-by-step explanation:

Let X is the number of non-authentic names in her sample with parameter :

n= 5 and p=40% = 0.40

Binomial probability distribution, the probability of getting success in x trials :-

$P(X=x)=^nC_xp^x(1-p)^{n-x}$

We have ,

$P(X=0)=^{5}C_0(0.40)^0(1-0.40)^{5}\\\\=(1)(0.60)^{5}\\\\=0.07776\approx0.0778$

Thus , the correct answer is option c. 0.0778

8 0

3 years ago