Source: Net
Let x represent the cost of a dozen roses. 5 dozen roses can be purchased for $62.50 . Consider the following equation. 5x = $62.50. Here the product and factor are known, thus divide by the factor on both sides of the equation.
5x $62.50
-- = --
5 $12.50
Now to find out the cost of 8 dozens multiply the value of x by 8.
8x=8 ($12.50) = $100
Answer would be $100.
Step-by-step explanation:
Selling price = Rs.80
Cost price = Rs.100
here, CP > SP
Now...
Loss ( L ) = CP - SP
= RS.100 - 80
= Rs.20
Now...


= 20 %
R/9 = -21
Multiply by 9
r = -189
Lets work backwards, he had $5 after it all, and spent $1.25 on a snack, so we add that to the remainder, which is $6.25. then he spent half of that on whatever stuff he likes, so add $6.25 and $6.25, which is $12.50