kotela
Mark bought a set of 6 flower pots of different sizes at a total cost of $8.25 each pot cost $0.25 more than the one below it in size,what was the cost in dollars of largest pot?
1. $1.75
2. $ 1.85
3 $2.00
4. $2.15
5. $ 2.30
I got A, but it is wrong, please help
Just to give you an alternative method, try back solving if it suits you.
I looked at the options and picked $2.00 (since it is right in the middle so even if it is not my answer, I would have eliminated 3 options after I am done with it. (I will explain you what I mean at the end.)
If largest pot cost $2, fifth largest cost 1.75, fourth largest cost 1.5 and third largest cost 1.25
The average cost of all 6 pots will be right in the middle of 1.25 and 1.5 which is 1.375 (All of this can be done in your head.)
Now all we need to do on paper is figure out 1.375 * 6 which does come out to be 8.25 (or if you like innovative ways of calculating, think that 1.25*6 is 7.5 and 1.5*6 is 9.0 so 1.375*6 must be right in the middle i.e. 8.25). Hence the largest pot must have cost $2.00
This method is very fast if you are quick in your calculations.
Here, fortunately, the first option we picked gave us the answer. It may not always happen. Say, if instead of 8.25, we get 8, we know the largest pot must have cost more so possible answers are 2.15 and 2.30. Pick either one of them and check.