As part of a competition a whole school years of 420 pupils were asked to write an essay. They could choose from 3 general topics that were: Science, English and a story. If #1/3# of them chose Science and #1/6# chose English how many chose story?

1 Answer
Apr 2, 2017

Answer:

#210#

Explanation:

#color(blue)("Method 1")#

Science #->1/3xx420 = 140#
English #->1/6xx420=70#

Story #=420-140-70 = 210#
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#color(blue)("Method 2")#

Not story proportion #=1/3+1/6" " =" " 2/6+1/6" " =" " 3/6" "=" "1/2#

So story #->(1-1/2)xx420" " =" " 1/2xx420" "=" "210#