Answer:
29/30
Step-by-step explanation:
Make all denominators equal to 30.
4/5 × 6/6 + 1/2 × 15/15 - 1/3 × 10/10
24/30 + 15/30 - 10/30
Combine.
(24 + 15 - 10)/30
(24 + 5)/30
= 29/30
18 / test2 *100 = 150
test2 = 1800/150
test2 = 12
so 12 students received a on the second test.
5x + 2y = 30
x + y = 8 <==== multiply by -2
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5x + 2y = 30
-2x - 2y = -16 (result of multiplying by -2)
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3x = 14....u see how multiplying by -2 will eliminate the y's