百分數與變分

Find the amount (correct to the nearest dollar) of $\$10\,000$ at $12\%$ p.a., compounded monthly, for 2 years.

If a flat is sold for $\$720\,000$, the gain is $20\%$. Find the percentage loss if the flat is sold for $\$540\,000$.

If $A$ is $30\%$ greater than $B$ and $B$ is $30\%$ less than $C$, then

Which of the following graphs shows that $y$ is partly constant and partly varies inversely as $x$?

If $z$ varies inversely as $x$ and directly as $y$, then

If $A$ is greater than $B$ by $20\%$ and $B$ is smaller than $C$ by $30\%$, then

At the beginning of a year, a man borrows $\$1000$ from a bank at $5\%$ per annum, compounded yearly. He promises to repay $\$300$ at the end of each year. How much will he still owe the bank just after the second repayment?

Given that $y\propto\dfrac{1}{x}$, if $x$ increased by $25\%$, find the percentage change in $y$.

The costs of two kinds of coffee $A$ and $B$ are $\$12$/kg and $\$20$/kg respectively. In what ratio by weight should $A$ and $B$ be mixed so that the mixture will cost $\$15$/kg?

$y$ varies inversely as $x^2$. If $x$ is increased by $100\%$, then $y$ is