Question

plz solve Q. no.9,10 and 11​

Answer 1

9.

Cost Price (CP) ⇒ Rupees 200

Profit ⇒ 20%  

Profit ⇒  $\frac{20}{100} \times 200 = 40$

Now we know that...

Amount the book was sold at to Rohan ⇒ $200+40=\bf Rupees\ 240$

The book was sold to Rishi at 10% loss ⇒ $240\times \frac{10}{100} = 24$

Amount the book was sold at to Rishi ⇒ $240-24 =\bf Rupees\ 216$

∴ Rishi paid Rs.216 for the book.

10.

Cost of 8 books = Selling price of 6 books

Let the cost price of 1 book be ⇒ $x$

So now, the cost price of 6 books would be ⇒ $6x$

Now we know that, selling price of 6 books = cost price of 8 books = 8x

Gain = $sp-cp$

Gain = $8x-6x =2x$

Gain Percentage ⇒ $\frac{Gain}{Cost\ Price } \times 100$

Gain Percentage ⇒ $\frac{2x}{6x}\times 100$

Gain Percentage ⇒ $\frac{100}{3}=33.333....\%$

∴ The gain percentage is 33.333...%

11.

Cost Price of 10 eggs ⇒ Rupees 8

Cost Price of 1 egg ⇒ $\frac{8}{10} = \frac{4}{5}$

Selling Price of 8 eggs ⇒ Rupees 10

And, selling price of 1 egg ⇒ $\frac{10}{8} = \frac{5}{4}$

Profit = S.P - C.P

⇒ $\frac{5}{4} - \frac{4}{5}$

⇒ $\frac{(25 - 16)}{20}$

⇒ $\frac{9}{20}$

Profit percentage = $(\frac{9}{20} )\div \frac{4}{5} \times 100$

⇒ $(\frac{9}{20} )\times \frac{5}{4} \times 100$

⇒ $\frac{225}{4} \%$

⇒ $56.25 \%$

∴ The gain percentage is 56.25%