Answer:
27 children
Step-by-step explanation:
For every 9 children, there are 4 adults. Those numbers added together equal 13. Now, if we divide the total number of adults and children by 13, we will get the number of how many groups there are of 9 kids and 4 adults.
39 / 13 = 3
There are 3 groups of 9 kids and 4 adults, which means to find the total number of children, we have to multiply 3 by 9.
3 * 9 = 27
Therefore, there are 27 children total. I know this was probably really confusing, but I hope it helped in some way! Have a lovely day!! :)
Answer:
1 and 1/8 hours or
Step-by-step explanation:
Natasha spent one and a half hours on the beach, which can be rewritten as 3/2 hours. Out of that time, she spent 3/4 sleeping. The total time she spent sleeping on the beach is determined by the product of the amount of time she spent on the beach by the fraction of that time she spent asleep:

Natasha was asleep on the beach for 1 and 1/8 hours or 1 hour 7 minutes and 30 seconds.
Answer:
x = -1/7
Step-by-step explanation:
Solve for x
9-17x-5-4x=7
Combine like terms
-21x +4 = 7
Subtract 4 from each side
-21x-4+4 = 7-4
-21x = 3
Divide each side by -21
-21x/-21 = 3/-21
x = -1/7
Check
9 - 17(-1/7) -5 -4(-1/7) =7
9 + 17/7 -5 + 4/7 =7
4 +21/7 = 7
4+3 = 7
7=7
1/10x + 6 = 2/5x
6 = 2/5x - 1/10x
6 = 4/10x - 1/10x
6 = 3/10x
6 / (3/10) = x
6 * 10/3 = x
60/3 = x
20 = x <=== the gas tank can hold 20 gallons

It looks like your first selection (a) is appropriate.