document.write( "Question 984473: A, B and C are three groups of pupils. If group A is 1/3 of the total number of pupils in the three groups, Group B has 5 pupils more than group A and group C has 3/5 as many pupils as group B, find the original number of pupils in each group. \n" ); document.write( "
Algebra.Com's Answer #605314 by ankor@dixie-net.com(22740)\"\" \"About 
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A, B and C are three groups of pupils. If group A is 1/3 of the total number of pupils in the three groups, Group B has 5 pupils more than group A and group C has 3/5 as many pupils as group B, find the original number of pupils in each group.
\n" ); document.write( ":
\n" ); document.write( "Write an equation for each statement:
\n" ); document.write( "\" group A is 1/3 of the total number of pupils in the three groups,\"
\n" ); document.write( "a = \"1%2F3\"(a+b+c)
\n" ); document.write( "3a = a + b + c (multiplied both sides by 3)
\n" ); document.write( "3a - a = b + c
\n" ); document.write( "2a = b + c
\n" ); document.write( "\" Group B has 5 pupils more than group A\"
\n" ); document.write( "b = a + 5
\n" ); document.write( "or
\n" ); document.write( "a = b - 5
\n" ); document.write( "\"group C has 3/5 as many pupils as group B,\"
\n" ); document.write( "c = \"3%2F5\"b
\n" ); document.write( "c = .6b (decimals will work here)
\n" ); document.write( ":
\n" ); document.write( "In the 1st equation, 2a = b + c, replace c with .6b and replace a with (b-5)
\n" ); document.write( "2(b-5) = b + .6b
\n" ); document.write( "2b - 10 = 1.6b
\n" ); document.write( "2b - 1.6b = 10
\n" ); document.write( ".4b = 10
\n" ); document.write( "b = 10/.4
\n" ); document.write( "b = 25
\n" ); document.write( "then
\n" ); document.write( "a = 25 - 5
\n" ); document.write( "a = 20
\n" ); document.write( "and
\n" ); document.write( "c = .6(25)
\n" ); document.write( "c = 15
\n" ); document.write( ":
\n" ); document.write( "find the original number of pupils in each group.
\n" ); document.write( "a = 20; b = 25 ; c = 15
\n" ); document.write( ":
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\n" ); document.write( "See if that checks out in the 1st statement
\n" ); document.write( " group A is 1/3 of the total number of pupils in the three groups,\"
\n" ); document.write( "20 = \"1%2F3\"(20+25+15)
\n" ); document.write( "20 = \"1%2F3\"(60)
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