Which of the following best approximates the value of q if 5^28+3^11=5^q ?
Notice that 5^28+5^28+5^28+5^28+5^28 = 5*5^28 = 5^29
So 5^28 + 3^11 is much smaller than 5^29, but is clearly larger than 5^28, so q is closest to 28.
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