The sum of one fifth of a number and three is equal to half of the number. what is the number? a.5. b.10. c.15 d.20

1/5x +3 = 1/2x

x/5+3 = x/2

x/5-x/2 +3 =0

2x/10-5x/10 +3 =0

-3x/10 + 3=0

-3x/10 has to equal -3

-3 * x = 30

x=10

people grow faster than other people.

step-by-step explanation:

should you really be posting this isn't math boi.

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.