Ask question

Ask question

All categories

3 years ago

6

One pump fills a tank in 20 hours and another in 15 hours. When a third pump is added the tank fills in 6 hours. Find out how lo

ng it takes the 3rd pump to fill the tank alone.

1 answer:

mrs_skeptik [129]3 years ago

4 0

Every hour, the first pump fills 1/20 of the tank, and the second fills 1/15 of the tank. If, when combined with the third pump, all three pumps fill 1/6 of the tank in an hour, the third pump fills 1/6-1/15-1/20= $\frac{1}{20}$ of the tank every hour, so it takes a total of 20 hours to fill the tank alone.

You might be interested in

I need help ont his question

Ivahew [28]

Answer:x^2-y^2

Step-by-step explanation:

(x+y)(x-y) = x^2 -xy +xy -y^2 so it becomes x^2-y^2

3 0

3 years ago

If a math problem asks 3/4 the size of something do u multiply

galben [10]

Answer:

yeah

Step-by-step explanation:

explaining this is not fun but yes you lultiply

5 0

3 years ago

Finding Hypotenuse Lengths. Find the length of the hypotenuse.

ioda

Answer:

11) $\frac{3\sqrt{5}}{2}$

12) $4\sqrt{5}$

13) $22$

14) $18$

15) $2$

16) $24\sqrt{3}$

Step-by-step explanation:

For these problems I used the pythagorean theorem: $a^{2}+ b^{2}= c^{2}$ and SOHCAHTOA

Sin = $\frac{opposite}{hypotenuse}$

Cos = $\frac{adjacent}{hypotenuse}$

Tan = $\frac{opposite}{hypotenuse}$

11)

First find the length of the bottom side by using Cos

$cos(60)=\frac{x}{3}$

$3(cos(60))=x$

$1.5=x$

Then plug it into the formula for the pythagorean theorem to find the hypotenuse

$3^{2}+ 1.5^{2}= c^{2}$

$9+2.25=c^{2}$

$\sqrt{11.25}=\sqrt{c^{2}}$

$\frac{3\sqrt{5}}{2}$

12)

Find the length of the bottom side using Cos

$cos(60)=\frac{x}{8}$

$8(cos(60))=x$

$4=x$

Then plug it into the formula for the pythagorean theorem to find the hypotenuse

$8^{2}+ 4^{2}= c^{2}$

$64+16=c^{2}$

$\sqrt{80} =\sqrt{c^{2} }$

$4\sqrt{5}$

13)

Find the length of the other side by using Tan

$tan(30)=\frac{x}{11\sqrt{3} }$

$11\sqrt{3}* (tan(30)=x$

$11=x$

Then plug it into the formula for the pythagorean theorem to find the hypotenuse

$(11\sqrt{3}) ^{2}+ 11^{2}= c^{2}$

$363+121=c^{2}$

$\sqrt{484} =\sqrt{c^{2}}$

$22$

14)

(This is probably an easier way to do these problems)

Find the hypotenuse by using Cos ( $\frac{adjacent}{hypotenuse}$ )

$cos(60)=\frac{9}{x}$

$cos(60)x=9$

$x=\frac{9}{cos(60)}$

$x=18$

15)

Find the hypotenuse using Sin ( $\frac{opposite}{hypotenuse}$ )

$sin(30)=\frac{1}{x}$

$sin(30)x=1\\x=\frac{1}{sin(x)}$

$x=2$

16)

Find the hypotenuse using Cos ( $\frac{adjacent}{hypotenuse}$ )

$cos(60)=\frac{12\sqrt{3} }{x}$

$cos(60)x=12\sqrt{3}$

$x=\frac{12\sqrt{3} }{cos(60)}$

$x=24\sqrt{3}$

5 0

4 years ago

One type of insect is 0.0052 meter long. what is the length in scientific notation.

sp2606 [1]

Here, we need to write the length of the insect in scientific notation.

The given length of the insect is 0.0052 meter

Now, to write 0.0052 meter in scientific notation we need to follow this:

Scientific notation always start with non-zero digit followed by a decimal point.

Since in our number the decimal is needed to be moved three places to the right to get the first non-zero digit.

The exponent of the 10 is $-3$ .

$10^{-3}=\frac{1}{1000} =0.001$

Therefore, our number 0.0052 can be written as:

$5.2 \times 10^{-3}$

Hence, the require scientific notation is $5.2 \times 10^{-3}$ .

7 0

3 years ago

How to find a circumference of a circle

Dahasolnce [82]

Answer:

2πr is the formula to calculate

Step-by-step explanation:

8 0

3 years ago

Read 2 more answers