Question 177810: I am not sure how to do solve these problems.
*In a College Algebra class, the final exam is 20% of the course grade. If Greg's regular exam scores are 80, 64, 88, 92, and 85, what does he need to make on the final exam to make a B (80%) in the course?
*At fine restaurants, a 15% gratiuty is added to the check by the management. If your bill comes to $93.89, how much did the meal alone cost?
*At Bob's Fish House, small shrimp cost $4 per pound and large shrimp cost $6.50 per pound. A customer wishes to pay exactly $75 (before tax) for 15 pounds of a mixture of shrimp. How many pounds of large and small shrimp should Bob package for the customer?
Answer by Mathtut(3670)   (Show Source):
You can put this solution on YOUR website! *In a College Algebra class, the final exam is 20% of the course grade. If Greg's regular exam scores are 80, 64, 88, 92, and 85, what does he need to make on the final exam to make a B (80%) in the course?
*At fine restaurants, a 15% gratiuty is added to the check by the management. If your bill comes to $93.89, how much did the meal alone cost?
*At Bob's Fish House, small shrimp cost $4 per pound and large shrimp cost $6.50 per pound. A customer wishes to pay exactly $75 (before tax) for 15 pounds of a mixture of shrimp. How many pounds of large and small shrimp should Bob package for the customer?
:
1)We must assume that the other test make up 80%(and are equally weighted) of the his overall score..since there is no homework or quizzes involved here
:
so lets call x what he needs to score on the final exam
:
.8((80+64+88+92+85)/5)+.2x=80
:
.8(81.8)+.2x=80
:
65.44+.2x=80
:
.2x=14.56
:
 %,needs this score to get a B
:
:
*At fine restaurants, a 15% gratiuty is added to the check by the management. If your bill comes to $93.89, how much did the meal alone cost?
:
let x be the cost of the meal
:
x+.15x=93.89
:
1.15x=93.89
:
 dollars, cost of meal
:
:
*At Bob's Fish House, small shrimp cost $4 per pound and large shrimp cost $6.50 per pound. A customer wishes to pay exactly $75 (before tax) for 15 pounds of a mixture of shrimp. How many pounds of large and small shrimp should Bob package for the customer?
:
let x and y be the number of pounds of small and large shrimp respectively
:
x+y=15.......eq 1
4x+6.5y=75...eq 2
:
lets rewrite eq 1 to x=15-y and plug that value into eq 2
:
4(15-y)+6.5y=75
:
60-4y+6.5y=75
:
2.5y=15
:
 pounds of large shrimp
:
 pounds of small shrimp
|
|
|
