To solve this problem we can make a proportion.
6 5
-- = ---
10 x
to solve this proportion we can cross multiply and divide.
5 times 10 is 50. divided by 6 is 8.3
it will take her 8.3 minutes to run 5 laps
Answer:
1500 students
600 boys
Step-by-step explanation:
40% are boys, so 60% are girls.
Writing a proportion:
900 / 60% = x / 100%
x = 1500
There are 1500 students in the school, which means there are 600 boys in the school.
Answer:

Step-by-step explanation:

we can use the distributive property and get

and we can add like terms

and know we divide both sides by 16.5

and doing the dvision we get that

The computer cost is $3000
Step-by-step explanation:
The given is:
- The ratio of the price of a tv to the price of a computer is 13 : 15
- The tv 400 dollars cheaper than the computer
We need to find the cost of the computer
Assume that the price of the computer is $x
∵ The ratio between the prices of the tv and the computer is 13 : 15
∵ The price of the computer is $x
∵ The price of the tv 400 dollars cheaper than the computer
- That means the price of the tv is less than the price of the
computer by $400
∴ The price of the tv is $(x - 400)
By using the ratio method
→ tv : computer
→ 13 : 15
→ (x - 400) : x
By using the cross multiplication
∴ 15(x - 400) = 13(x)
- Simplify the left hand side
∴ 15x - 6000 = 13x
- Add 6000 to both sides
∴ 15x = 13x + 6000
- Subtract 13x from both sides
∴ 2x = 6000
- Divide both sides by 2
∴ x = 3000
The computer cost is $3000
Learn more:
You can learn more about the ratio in brainly.com/question/4847829
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