A steel plate has a length of 1.5 feet, a width of 1 foot, and a thickness of 3/4 inch. A drill makes a hole in the plate with a 1-inch diameter. What is the surface area of the steel plate? Round your answer to the nearest inch.
Actually, the answer is given to me as 477 square inches, but HOW?
Thanks.
Actually, the answer is given to me as 477 square inches, but HOW?
Thanks.
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Jim's answer forgets one small thing. You must subtract the area of the two circles where the hole has removed some of the plate.
so the area is
2 * (length * height + width * height + length * width - area of circle) + area of cylinder wall.
= 2 * (12* 3/4 + 18 * 3/4 + 12* 18 - pi()*0.5^2 ) +pi()* 1 * 3/4
=477.7854 inch^2
so the area is
2 * (length * height + width * height + length * width - area of circle) + area of cylinder wall.
= 2 * (12* 3/4 + 18 * 3/4 + 12* 18 - pi()*0.5^2 ) +pi()* 1 * 3/4
=477.7854 inch^2
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2 x (area of top + area of side + area of end) + area of cylinder side
edit: Andrew is correct. My answer is 1.6 sq.in. too large.
edit: Andrew is correct. My answer is 1.6 sq.in. too large.