Answer:

Step-by-step explanation:
As given
if n erasers have a weight of 80 grams .
I.e
n erasera = 80 grams.
1 erasers weight .

Now find out the weight of the 50 erasers.

Simplify the above


1/14 is you answer
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(4a + 6b) x (2a - 2b)
the answer would be 8a2 + 4ab - 12b2
Direct variation is when one variable changes the other changes in proportion of the first, therefore all the above