ANSWER

EXPLANATION
We want to find the value of a for which the binomial, 2a-1 is smaller than the value of the binomial 7-1.2a by 7.
This means that, when we subtract 2a-1 from 7-1.2a, we should get 7.

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Group similar terms:


Divide both sides by -3.2,


3276800/8 = 409600 (how many bacteria in an hour)
Then just multiply that number by the amount of hours you want to solve for
9 hours = 3686400
10 Hours = 4096000
15x20=300
300 square feet is 33.33333333333333333333333333333333333 square yards (divide by 9)
the answer is 33