Answer: $222.73
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Work Shown:
x = pre-GST price
10% of x = 0.10x = tax amount
x + 0.10x = 1.10x = post-GST price = 245
1.10x = 245
x = 245/1.10
x = 222.7272 approximately
x = 222.73 is the price before tax.
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Check:
10% of 222.73 = 0.10*222.73 = 22.273 = 22.27
The tax amount ($22.27) is added to the pre-GST price to get
22.27+222.73 = 245
which matches the post-GST price mentioned.
The answer is confirmed.
Or another way to confirm the answer is to calculate this
1.10*222.73 = 245.003 = 245
1 is the whole number which means it goes before the decimal point. 2/10 is the fractional piece making it go after the decimal point in the tenths place.
1 2/10 = 1.2
If he swan the length and the width of the pool it would be 21 x28 = 588 sq ft.
by swimming the length and the diagonal of the pool (25 ft) found that by using the pythagorean therom so now you are multiplying 21 x 25 = 525
588-525= 63 ft he is saving