Answer:
3. A single translation
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
First recognize that the unit rate we're finding is gallons per hour, or

.
rate for Tank 1 = x gallons per hour = <em>a</em> gallons / <em>b</em> hours

rate for Tank 2 = y gallons per hour = <em>c</em> gallons / <em>d</em> hours
So we solve for each
70% of 100=70
students who didn't buy lunch=100-70=30
some of the 70 left so that the students who bought lunch, are 60% of those who are left
we know that the students who didn't buy lunch didn't change number so therefor
100% of students left-60%=40%= students that didn't buy lunch=30 so
40%=30
20%=15
100%=75
there were 75 students lfet in the cafeteria