Question

3/5 of the students ride the bus, what percent does not?

Answer 1

The answer is: " 40 % " .
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Note:
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If "3/5" of the students ride the bus, then "2/5" do not ride the bus".

Since: "3/5" + "2/5" = "(3 + 2)" / 5 = 5/5 = "1" (as in "1 whole").

1 – (3/5) = (5/5) – (3/5) = (5 – 3) / 5 = 2/5.
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Now, express: "2/5" as a percentage ;

→ "2/5" = "x / 100 " ; Solve for "x"

Cross-multiply: Note:

→ Given: "
`(a)/(b)`" = "
`(c)/(d)`" ;

→ " bc = ad" ; {" b
`\\eq`0 ; d
`\\eq`0 "} .
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As such:

→ "
`(2)/(5)`" = "
`(x)/(100)`" ;

→ " 5x = (2)*(100) " ; → Solve for "x" ;

→ " 5x = 200 " ;

→ Divide each side of the equation by "5" ;
to isolate "x" on one side of the equation; & to solve for "x" ;

→ " 5x / 5 = 200 / 5 " ;

to get:

→ " x = 40 " ;
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So; we have:


→ "2/5" = "40 / 100 " ;

→ "2/5" = " 40 % " .
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The answer is: " 40 % " .
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