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3 years ago

Twice the sum of a number and 5 is equal to three times the difference of the number and 7. Find the number.

Mathematics

1 answer:

Alexandra [31]3 years ago

5 0

Step-by-step explanation:

Let the required number be x.

According to the given information:

$2(x + 5) = 3(x - 7) \\ \\ \therefore \: 2x + 10 = 3x - 21 \\ \\ \therefore \: 10 + 21 = 3x -2x \\ \\ \therefore \: 31 = x \\ \\ \huge \red { \boxed{\therefore \: x = 31}}$

Hence the required number is 31.

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Kabul’s bookshop marks up all books by 40 percent of their cost. The overhead rate is 16 percent of the selling price. What is t

morpeh [17]

Answer:

The net profit rate on the book is 5.41

Step-by-step explanation:

Given as :

The marks up percentage of book = m = 40%

The overhead rate is 16% of selling price

The cost price of book = c.p = $18.10

Let The profit = $p

Let The selling price = s.p

<u>Now, According to question</u>

mark up percentage = $\dfrac{s.p - c.p}{c.p}$

I.e 40% = $\dfrac{s.p - 18.10}{18.10}$

Or, $\dfrac{40}{100}$ + 1 = $\dfrac{s.p}{18.10}$

Or, $\dfrac{140}{100}$ = $\dfrac{s.p}{18.10}$

Or, s. p = $\dfrac{140\times 18.10}{100}$

∴ s.p = $25.34

So, selling price of book = s.p = $25.34

Now, The overhead percentage = 16%

i.e overhead rate = $\dfrac{\textrm estimated cost}{\textrm estimated total base unit}$

Or, estimated cost = 16% × 25.34

I,e estimated cost = 0.16 × 25.34

∴ estimated cost = $4.05

Now,

Profit = selling price of book - estimated book cost

I.e p = $25.34 - $4.05

∴ p = $21.29

So, The profit rate% = $\dfrac{\textrm profit}{\textrm estimated cost}$

I.e The profit rate% = $\dfrac{21.29}{4.05}$

∴ profit rate %= 5.41

So, The profit rate = p = 5.41

Hence, The net profit rate on the book is 5.41 Answer

4 0

2 years ago

18 Ib= oz plz help me mann

Nataliya [291]

There are 288 ounces in 18 lbs

6 0

2 years ago

Read 2 more answers

{3.1, 4.2, 7.2, 8.4, 12.2}

Romashka-Z-Leto [24]

X + 2 = 6.2
subtract 2 from both sides
x = 4.2

6 0

3 years ago

hannahs hourly wage at the icecream shop is $5.85. the table shows the number of hours she worked. She estimates her earnings to

____ [38]

109.69 is act ual so her estimate is more

5 0

2 years ago

Over the course of the school year, you keep track of how much snow falls on a given day and whether it was a snow day. Your dat

Free_Kalibri [48]

Answer:

Probability of the day to be a snow day is 0.34

Step-by-step explanation:

We have the data,

Out of 21 which had less than 3 inches of snow, 5 were snow days.

Out of 8 days which had more than 3 inches of snow, 6 were snow days.

So, we get,

Total number of days = 21 + 8 = 29

Total number of snow days = 5 + 6 = 11

Thus, the probability that the day will be a snow day is $\frac{11}{29}$ i.e. 0.34

Hence, the probability of the day to be a snow day is 0.34.

5 0

2 years ago