document.write( "Question 1173955: squares, circles and pentagons in the ratio 3:4:1 respectively.
\n" ); document.write( "The shapes are either made of wood or plastic.
\n" ); document.write( "The ratio of wood squares to plastic squares is 3:2.
\n" ); document.write( "25% of the circles are wood.
\n" ); document.write( "2/3 of the pentagons are wood.
\n" ); document.write( "If there are 27 wood squares, how many plastic shapes are there?
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Algebra.Com's Answer #799289 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "Let's label each sentence as fact 1 through fact 6
  • Fact 1) squares, circles and pentagons in the ratio 3:4:1 respectively.
  • Fact 2) The shapes are either made of wood or plastic.
  • Fact 3) The ratio of wood squares to plastic squares is 3:2.
  • Fact 4) 25% of the circles are wood.
  • Fact 5) 2/3 of the pentagons are wood.
  • Fact 6) There are 27 wood squares
From fact 3 and fact 6, we can say
\n" ); document.write( "(27 wood squares)/(x plastic squares) = 3/2
\n" ); document.write( "27/x = 3/2
\n" ); document.write( "27*2 = x*3
\n" ); document.write( "54 = 3x
\n" ); document.write( "3x = 54
\n" ); document.write( "x = 54/3
\n" ); document.write( "x = 18
\n" ); document.write( "There are 18 plastic squares.
\n" ); document.write( "Let A = 18 since we'll use it later.
\n" ); document.write( "There are 27+18 = 45 squares overall.\r
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\n" ); document.write( "\n" ); document.write( "Let y be some positive whole number.
\n" ); document.write( "The ratio 3:4:1 is equivalent to 3y:4y:1y when we multiply both parts by y.\r
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\n" ); document.write( "\n" ); document.write( "This new ratio says that we have 3y squares, 4y circles, and 1y pentagons. Earlier we found that we have 45 squares.
\n" ); document.write( "So,
\n" ); document.write( "3y = 45
\n" ); document.write( "y = 45/3
\n" ); document.write( "y = 15\r
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\n" ); document.write( "\n" ); document.write( "This y value leads to
\n" ); document.write( "3y = 3*15 = 45 squares
\n" ); document.write( "4y = 4*15 = 60 circles
\n" ); document.write( "1y = 1*15 = 15 pentagons
\n" ); document.write( "The ratio 45:60:15 reduces to 3:4:1 when you divide all three parts by the GCF 15.\r
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\n" ); document.write( "\n" ); document.write( "25% of the circles are wood (fact 4), so
\n" ); document.write( "25% of (60 circles) = 0.25*60 = 15
\n" ); document.write( "We have 15 wood circles and 60-15 = 45 plastic circles.
\n" ); document.write( "Let B = 45 since we'll need it later.\r
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\n" ); document.write( "\n" ); document.write( "Earlier we found there are 15 pentagons. Two-thirds of those pentagons are wood (fact 5), which means (2/3)*15 = 10 pentagons are wood and 15-10 = 5 pentagons are plastic.
\n" ); document.write( "Let C = 5.\r
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\n" ); document.write( "\n" ); document.write( "The values of A,B,C were aimed to collect all the plastic shape counts
\n" ); document.write( "A+B+C = 18+45+5 = 68\r
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\n" ); document.write( "\n" ); document.write( "There are 68 plastic shapes\r
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\n" ); document.write( "\n" ); document.write( "Answer: 68
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