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2 years ago

Divide 72 in the ratio 3:4:5

Mathematics

2 answers:

Sophie [7]2 years ago

6 0

Answer:

18, 24, 30

Step-by-step explanation:

Here are two methods of solving this problem.

We can do this by trial and error.

The ratio needs to be 3:4:5 with a sum of 72.

Try 3 + 4 + 5 = 12. That is way too small.

Multiply each number by 4:

4 * 3 = 12

4 * 4 = 16

4 * 5 = 20

Now add the products: 12 + 16 + 20 = 56. That is closer.

Try multiplying the numbers in the ratio by 6.

6 * 3 = 18

6 * 4 = 24

6 * 5 = 30

Add the products: 18 + 24 + 30 = 72

That is the answer.

Answer: 18, 24, 30

We can do this with an equation.

We know we need to multiply the three numbers in the ratio by a number, but we don't know what that number is. Let's call the multiplier x.

The numbers in the ratio become

We want their sum to be 72.

3x + 4x + 5x = 72

12x = 72

x = 72/12

x = 6

Now we know the multiplier is 6.

6 * 3 = 18

6 * 4 = 24

6 * 5 = 30

Answer: 18, 24, 30

ziro4ka [17]2 years ago

3 0

Answer:

Total number of parts = 3 + 4 + 5. = 12 parts. Each part = 72 ÷ 12.

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3 years ago

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Answer:

(a).

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(b).

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3 years ago

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3 years ago

Read 2 more answers

Write the equation in standard form of a circle with center (-7,2), tangent to the y-axis.

Vesna [10]

Answer:

$(x+7)^2+(y-2)^2=7^2$

Step-by-step explanation:

Tangent to y-axis means that the side of the circle TOUCHES the y axis.

Since the center is at (-7,2) and it touches the y axis, we can figure out the radius. It goes from (-7,2) to y-axis. Horizontally, the center is 7 units left of y-axis, so that is the radius ----- 7 units

The standard form of a circle is:

$(x-h)^2+(y-k)^2=r^2$

Where

(h,k) is the center

r is the radius

Putting the information into the form, we have:

$(x-h)^2+(y-k)^2=r^2\\(x-(-7))^2+(y-(2))^2=7^2\\(x+7)^2+(y-2)^2=7^2$

THis is the standard form.

7 0

3 years ago

Divide 72 in the ratio 3:4:5​

Divide 72 in the ratio 3:4:5