Percentage

[Guest]

Hi everyone please provide me the solution for the following problems on probability.Also please give me the valid and good explanation for the how you are arriving to the answers.Actually i am not finding good explanation for these problems in the book.

1.
Robert has 12coins totalling $1.45.None of his coins is larger than a quarter.What can be the least numner of quarter he has?

2.
Mr cutler usally makes 45% profit on every radio he sells.During a sale he reducs margin of profit to 40% while his sals increase by 10%.What is the ratio of his total profit to original profit.

Thanks,
S.

[shyamjayakannan]

for the second problem, let the cost price be [tex]c[/tex]. So, original selling price [tex]s_1=1.45c[/tex] and new selling price [tex]s_2=1.4c[/tex].
Let the number of items sold originally and later be [tex]n_1[/tex] and [tex]n_2=1.1n_1[/tex], respectively.

Now, total original profit = [tex]n_1\left(s_1-c\right)=0.45n_1c[/tex] and total new profit = [tex]n_2\left(s_2-c\right)=0.44n_1c[/tex].

So, ratio of new profit to original profit = [tex]\frac{0.44}{0.45}=\boxed{0.97}[/tex]