EXERCISE 8.3

Juhi sells a washing machine for $₹13,500.$ She loses $20\%$ in the bargain. If the price at which she bought it was $₹k$, find the value of $k$.

Chalk contains calcium, carbon and oxygen in the ratio $10:3:12$. Find the percentage of carbon in chalk.

 Chalk contains calcium, carbon and oxygen in the ratio $10:3:12$. If in a stick of chalk, carbon is $3 \mathrm{g}$ and the weight of the chalk stick is $x \mathrm{g}$, find $x$.

Amina buys a book for $₹275$ and sells it at a loss of $15\%.$ How much does she sell it for?  [ write only numerical value without rupee symbol]

If the amount to be paid at the end of $3$ years when Principal $=₹1,200 \mathrm{at} 12\mathrm{\%} \mathrm{p}.\mathrm{a}$ is $₹k$. Find the value of $k$

If the amount to be paid at the end of $3$ years is $₹k$, when Principal $=₹7500 \mathrm{at} 5\mathrm{\%} \mathrm{p}.\mathrm{a}.$, then find the value of $k$.

What rate gives $\mathrm{Rs} 280$ as interest on a sum of $\mathrm{Rs} 56,000$ in $2$ years?

If Meena gives an interest of $₹45$ for one year at $9\%$ rate p.a. then the sum she has borrowed is $₹k$. Hence, find the value of $k$.