SOLUTION: Please help me. I got 42% in my lab report which is worth 30%. I got 50% in my second lab report which is also worth 30%. What do i need in my exam which is worth 40% to achieve a

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Question 875844: Please help me. I got 42% in my lab report which is worth 30%. I got 50% in my second lab report which is also worth 30%. What do i need in my exam which is worth 40% to achieve a overall of 60%? Many thanks please reply it's important.
Found 2 solutions by ewatrrr, Theo:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
.30•42 +.30•50 +.40x = 60

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the score on your final exam will be found by using the following equation.

.30 * 42 + .30 * 50 + .40 * x = 60

simplify this equation to get:

12.6 + 15 + .40 * x = 60

subtract 12.6 and 15 from both sides of this equation to get:

.40 * x = 60 - 12.6 - 15

simplify to get:

.40 * x = 32.4

divide both sides of this equation by .40 to get:

x = 32.4 / .40 which becomes:

x = 81

you need an 81 on final exam in order to get an overall grade of 60% from your grades.

.30 * 42 + .30 * .5 + .40 * 81 = 12.6 + 15 + 32.4 = 60

your answer is confirmed as good.

you need an 81 on your final exam.