Answer:
b. 256 m²
d. 324 cm²
f. 35 in²
Explanation:
b.
The shaded area is the difference between the areas of the outer rectangle and the inner one:
A = (24 m)(12 m) -(8 m)(4 m) = 288 m² -32 m² = 256 m²
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d.
The steps are all the same height and width. Their height is (18 cm)/3 = 6 cm, so the height of the middle step is 2×6 cm = 12 cm. The area of the figure will be the product of the base and the average step height:
A = (27 cm)(12 cm) = 324 cm²
You might be able to visualize this as cutting off the top step even with the middle on and placing it on top of the bottom step.
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f.
The triangle area formula applies.
A = 1/2bh = 1/2(4" +10")(5") = 35 in²
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Additional comment
The formula for area of a rectangle is ...
A = LW . . . . . the product of length and width