All categories

2 years ago

If you can paint 75 square feet every 45 minutes how long will it take to paint a 8 by 5

Mathematics

2 answers:

Helga [31]2 years ago

7 0

Answer:

24 minutes

Step-by-step explanation:

The Dimensions of the wall are given as:

8ft × 5ft = 40ft² or 40 square feet

Step-by-step explanation:

slava [35]2 years ago

3 0

Answer:

24 minutes

Step-by-step explanation:

8 * 5 = 40 ft²

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

Method I: Use a proportion

x/40 = 45/75

multiply both sides by 40

x = 45/75 * 40

x = 24

24 minutes

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

Method II: Use the rate

45/75 = 0.6min/ft²

40 * 0.6 = 24

24 minutes

You might be interested in

Use triangle ABC drawn below & only the sides labeled. Find the side of length AB in terms of side a, side b & angle C o

Brrunno [24]

Answer:

$AB = \sqrt{a^2 + b^2-2abCos\ C}$

Step-by-step explanation:

Given:

The above triangle

Required

Solve for AB in terms of a, b and angle C

Considering right angled triangle BOC where O is the point between b-x and x

From BOC, we have that:

$Sin\ C = \frac{h}{a}$

Make h the subject:

$h = aSin\ C$

Also, in BOC (Using Pythagoras)

$a^2 = h^2 + x^2$

Make $x^2$ the subject

$x^2 = a^2 - h^2$

Substitute $aSin\ C$ for h

$x^2 = a^2 - h^2$ becomes

$x^2 = a^2 - (aSin\ C)^2$

$x^2 = a^2 - a^2Sin^2\ C$

Factorize

$x^2 = a^2 (1 - Sin^2\ C)$

In trigonometry:

$Cos^2C = 1-Sin^2C$

So, we have that:

$x^2 = a^2 Cos^2\ C$

Take square roots of both sides

$x= aCos\ C$

In triangle BOA, applying Pythagoras theorem, we have that:

$AB^2 = h^2 + (b-x)^2$

Open bracket

$AB^2 = h^2 + b^2-2bx+x^2$

Substitute $x= aCos\ C$ and $h = aSin\ C$ in $AB^2 = h^2 + b^2-2bx+x^2$

$AB^2 = h^2 + b^2-2bx+x^2$

$AB^2 = (aSin\ C)^2 + b^2-2b(aCos\ C)+(aCos\ C)^2$

Open Bracket

$AB^2 = a^2Sin^2\ C + b^2-2abCos\ C+a^2Cos^2\ C$

Reorder

$AB^2 = a^2Sin^2\ C +a^2Cos^2\ C + b^2-2abCos\ C$

Factorize:

$AB^2 = a^2(Sin^2\ C +Cos^2\ C) + b^2-2abCos\ C$

In trigonometry:

$Sin^2C + Cos^2 = 1$

So, we have that:

$AB^2 = a^2 * 1 + b^2-2abCos\ C$

$AB^2 = a^2 + b^2-2abCos\ C$

Take square roots of both sides

$AB = \sqrt{a^2 + b^2-2abCos\ C}$

6 0

3 years ago

Find the volume of the solid. Round to the nearest tenth if necessary.

Vikki [24]

$V= \frac{4}{3} \pi r^{3} or V=4.1888 r^{3}$

r=4 $r^{3}$ =64*4.1888=268.083

V = 268.083 $mm^{3}$ so go with A.

7 0

2 years ago

There are ___ nuts are in the smallest possible container.

NARA [144]

Small is the blank which is th answer

8 0

3 years ago

Alan, david and shari are running for president of their high school. There were a total of 1,000 votes cast for president. Davi

vekshin1

Answer:

Alan received 350 votes

Step-by-step explanation:

David received 250 votes

Shari received 400 votes

1,000 - 250=750

750 - 400 = 350

7 0

3 years ago

Devon bought running shocs at a price that was 1/4 off the original price of $88. He paid a sales tax of 7% on

larisa86 [58]

The correct answer is C. $ 9.38

Explanation:

The first step to solve this mathematical problem is to know the price of the shoes. About this, we know the price is 1/4 of $88 plus taxes. You can find how much is 1/4 of $88 by following this process:

1. Write the amounts given

$\frac{1}{4}$ of $88$

2. Divide the number by the denominator (bottom number) and then multiply by the numerator

$88$ ÷ $4 = 22$

$22 x 1 = 22$

This means the discount was $22 and $88- $22 = $66, which is the price with the discount. Now, it is necessary to add the sales tax, which can be done by finding the 7% of $66 and adding this number to $66 (the price of the shoes including the 1/4 discount)

1. Write the values

66 = 100 (66 represents the total or 100%)

x = 7 (7% is the value you want to know and the x represents the value is not known)

2. Cross multiply

x 100 = 462

3. Find x

x = 462 ÷ 100

x = 4. 62 ( value of taxes)

Now, add the taxes to the price $66 + $ 4.62 = $70.62 (price with taxes). Finally, we know Devon paid using four $20 bills. This means he gave the clerk $80 ($20 x 4 = $80). Finally, to know how much is the change subtract the price of the shoes from the money Devon gave the clerk $80 - $70.62 = $9.38

4 0

3 years ago