
The square root of 729 is in fact 27, as it is a perfect square, but this is not well known, so we can figure it out like this:
What goes into 729 that are perfect squares? 81 and 9:

Take the square root of 81 (9) and the square root of 9 (3). Move these to the outside of the square root (they will multiply with 3 since 3 is multiplied to the square root in the original problem)

Now, just multiply:
If Jan bought 3 lamps for $23.59 each, and a sofa for $769.99, then we can add these prices together for the total amount Jan spent:
23.59 + 23.59 + 23.59 + <span>769.99 = $840.76
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Now we can find out how much sales tax she owes by multiplying the total cost by the sales tax rate:
$840.76 x 7.5% = <span>840.76 x 0.075 = $63.06
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Therefore the answer is B. $63.06
% increase = (final - initial) / initial * 100
= (131 - 92) / 92 * 100
= 39/92 * 100
= 3900/92
= 42.39%
In short, Your Answer would be 42.39%
Hope this helps!