Answer:
19 hours
Step-by-step explanation:
You have 279. First, devide the 279 by 9(dollar amount).
279/9 = 31
So combined they work 31 hours. Subtract 7 from this, since we know Katya worked 7 extra hours. Youll now have 24. (31-7 = 24)
Next, divide this number in half, which will get you what they both worked before Katya worked an extra 7 hours.
24/2 = 12.
Now that we know they both worked 12 hours, we can just add back the 7 hours Katya worked.
12+7 = 19.
So the answer to how many hours katya worked will be:
19 hours
