Say you bought 3 pizzas. If you ate #5/12# and Joe ate #1 1/4# how much is left for Jenn?

2 Answers
Jun 11, 2018

#1 1/3# is left

Explanation:

You need to subtract to subtract #5/12 and 1 1/4# from #3#.

You can do this by adding them together and then subtracting, or we can do it in one calculation.

#3-5/12-1 1/4" "larr# work with the whole numbers first

#= 2 - 5/12 -1/4" "larr# convert one whole number to #12/12#

#= 1+color(blue)(1)-5/12-1/4#

#= 1 +color(blue)(12/12)-5/12-1/4" "larr# find a common denominator

#= 1 + (color(blue)(12)-5-3)/color(blue)(12)" "larr# use equivalent fractions.

#= 1 4/12#

#=1 1/3" "larr# simplest form

Jenn is left with # color(green)( = 1 1/3# pizzas

Explanation:

No. of pizzas bought #color(green)(= 3#

Pizzas ate by me and Joe # = (5/12) +1 1/4#

Pizzas left for Jenn # = 3 - (5/12 + 1 1/4)#

#L C M # for # 4, 12 # is # 12#

#:. => (3 - 5/12- 5/4)#

#=> (3*12 - 5 -5*3)/12 #

#=> (36 - 5 - 15) /12 = (36-20) / 12#

#=> cancel(16)^color(red)(4)/ cancel(12)^color(red)(3) = 4/3 = color(green)(1 1/3#