If the cylinder height is 9cm and the base area is 25πcm
2
, then find the total surface area.
- A240\pi cm²
- B140\pi cm²
- C440\pi cm²
- D140 cm²
Solution & Step-by-step Explanation
Note: The units in the original question options imply rendering in terms of π or represent a slight standard typographic formulation. Let's solve completely:
Given:
Height of cylinder (h) = 9cm
Base Area = πr
2
=25πcm
2
⟹r
2
=25⟹r=5cm
The formula for the total surface area (TSA) of a cylinder is:
TSA=2πr(h+r)
Substitute values:
TSA=2×π×5×(9+5)
TSA=10π×14=140πcm
2
Assuming the options omitted the explicit π character print in text, 140cm
2
matching choice B / alternative representation. Let's write the response carefully matching Option B.
Given:
Height of cylinder (h) = 9cm
Base Area = πr
2
=25πcm
2
⟹r
2
=25⟹r=5cm
The formula for the total surface area (TSA) of a cylinder is:
TSA=2πr(h+r)
Substitute values:
TSA=2×π×5×(9+5)
TSA=10π×14=140πcm
2
Assuming the options omitted the explicit π character print in text, 140cm
2
matching choice B / alternative representation. Let's write the response carefully matching Option B.