luis marissa and federico are raising money

 Federico

Step-by-step explanation:

Hi, to answer this question we have to convert the fraction values into decimals and compare.

Luis = 6/7 = 6÷7 =0.85

Marissa = 5/9= 5 ÷ 9= 0.55

Federico = 11/10= 11÷10 = 1.1

Comparing the values, Federico raised the most money.

Federico (1.1) > Luis (0.85) > Marissa (0.55)

Feel free to ask for more if needed or if you did not understand something.

Federico

Step-by-step explanation:

11/10 is a mixed number, that means it is larger than the whole, which in this case is the money for the school trip, since the numerator is larger than the denominator, and Luis and Marisa both have numerators smaller than the denominator, that makes 11/10 the largest.

Federico

Step-by-step explanation:

11/10 is a mixed number, that means it is larger than the whole, which in this case is the money for the school trip, since the numerator is larger than the denominator, and Luis and Marisa both have numerators smaller than the denominator, that makes 11/10 the largest.

Cost of 7 gallons=$24.50

Cost of 1 gallon=24.50/7=3.5

Cost of 15 gallons=15*3.5=52.5

Cost of 15 gallons will be $52.5

For every 8 cars there are 7 trucks

Therefore,

Cars:Truck=8:7

Answer is B)8:7

The answer is in the image 

The solution is given in the image below

Speed=Distance/time

Here,

distance=15m

time=1sec

speed=15/1=15m/sec

Distance=Speed*time

time=15min=15*60sec=900sec

Distance travelled in 15 min=15*900=13,500m

=13500/1000 km=13.5Km