Answer:
3
Step by Step:
Subtract the tip ($6) from the total ($39)
11x=33
Then divide 33 by 11, leaving you with the value of x.
x=3
The lesson was 3 hours long.
Base area = 6 ( 1/2 x 6 x 5.2) = 93.6 cm²
Volume = base area x height = 93.6 x 17 = 1591.2cm ³
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Answer: Volume = 1591.2 cm³
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