Your question seems a bit incomplete, but for starters you can write

Expanding where necessary, recalling that

, you have

and you can stop there, or continue to rewrite in terms of the reciprocal functions,

Now, since

, the final form could also take

or
30% converted to a decimal is 0.30
310 x 0.3 = 93 students play an instrument
105 - 75 = 30 That should do it.
Answer:
196 ounces
Step-by-step explanation:
1 pound = 16 ounces
16 x 7 = 112
112 + 84 = 196 ounces
The answers are 2.4 hours and 20 hours
The equation you have is correct. To solve the next ones you use that equation and plug in the number of hours given. So for 31 hours of babysitting you’d do this:
12(32)+15c=420
384+15c=420
15c=36
c=2.4
Same thing for 10 hours babysitting
12(10)+15c=420
120+15c=420
15c=300
c=20