Frances left a 10​% tip on a meal. Including the​ tip, its cost was​ $24.20. What was the cost of the meal before the​ tip?

2 Answers
Feb 12, 2018

Answer:

#$22#

Explanation:

The total is equal to the cost of the meal plus the cost of the meal times the ten percent which would equal the tip.

#x=# the cost of the meal

#x * 10% = # the tip

So

#$24.20=x10%+x#

#24.2=x* 0.1+x" " -> # #10% = 10/100#

#24.2=x(0.1+1)#

#24.2=1.1x#

#24.2/1.1=x#

#x=22#

Feb 12, 2018

Answer:

The meal itself cost #$22#

Explanation:

This is an example of reverse percentage because you know the value AFTER an increase of #10%# has taken place, but you do not know the original amount.

You can use direct proportion to compare the corresponding values and percentages.

The cost of just the meal, #x,# represents #100%#

Once a tip of #10%# is added on, the value represents #110%#

We know that is #$24.20#

#x/100 = 24.20/110" "(larr "dollars")/(larr "percent")#

#x = (24.20 xx100)/110#

#x= $22#

Check.:

#10%# of #$22 = $2.20#

#$22+$2.20 = $24.20#