The answer is: [B]: " 5/16 in² " .
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Explanation:
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Formula for Area, "A", of a trapezoid:
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A = (½) * (b₁ + b₂) * h ;
or, write as: A = (b₁ + b₂)*h / 2 ;
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in which: A = Area of the trapezoid ;
b₁ = length of one of the bases of the trapezoid (choose any of the two);
b₂ = length of the other base of the trapezoid (the remaining one);
h = height of the trapezoid ;
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Given:
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b₁ = ¼ in ;
b₂ = ⅜ in ;
h = 1 in ;
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Find the Area:
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Plug in these values given into the formula;
and solve for the "Area" of the trapezoid:
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→ A = (½) * (b₁ + b₂) * h
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→ A = (½) * (¼ in + ⅜ in) * (1 in) ;
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→ (Note: Let us simplify: "(¼ in + ⅜ in)" ;
¼ + ⅜ = ??
¼ = ?/ 8 ?? ; → 8÷4 =2 ; 2*4 = 8 ;
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So, 1/4 = (1*2) / (4*2) = 2/8 ;
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So; (¼ in + ⅜ in) = 2/8 in + ⅜ in = (2+3)/8 in = ⅝ in.
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So rewrite:
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→ A = (½) * (¼ in + ⅜ in) * (1 in) ;
substituting: "( ⅝ in)" for "(¼ in + ⅜ in)" ; AS FOLLOWS:
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→ A = (½) * (⅝ in) * (1 in) ;
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→ A = [ (½) * (⅝) ] in² ;
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→ A = [(1*5) / (2*8)] in²
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→ A = 5/16 in² ; or, write as: 0.3125 in² ;
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→ Area = 5/16 in² corresponds to:
"Answer choice: [B]" .
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