For the exponential function $y=1.{43}^x$, identify

i. the growth/ decay factor $b$,

ii. the growth/decay rate $r$,

iii. the initial value $a$.

For the exponential function $y=3\times 0.{62}^x$, identify

i. the growth/ decay factor $b$,

ii. the growth/decay rate $r$,

iii. the initial value $a$.

For the exponential function $y=4\times {\left(\frac{2}{3}\right)}^x$, identify

i. the growth/ decay factor $b$,

ii. the growth/decay rate $r$,

iii. the initial value $a$.

For the exponential function $y=0.8\times 1.2^x$, identify

i. the growth/ decay factor $b$,

ii. the growth/decay rate $r$,

iii. the initial value $a$.

A jeweler estimates that the value of gold is increasing by $12\%$. Determine the growth factor of the value of gold.

A jeweler estimates that the value of gold is increasing by $12\%$.

Write a function to model the future value of a gold bracelet valued at $\pounds 300$ in $2015$.

A jeweler estimates that the value of gold is increasing by $12\%$.

Write a function to model the future value of a gold bracelet valued at $\pounds 300$ in $2015$.

If the value of the bracelet in $2030$ is $\pounds k$, then the value of $k$ is ..... (Round off and write up to $2$ decimal places)

An electrical store calculates that the number of DVD players sold is decreasing by $22\%$ per year. In $2010$ they sold $470$ DVD players.

Write a function to model the future DVD sales.

An electrical store calculates that the number of DVD players sold is decreasing by $22\%$ per year. In $2010$ they sold $470$ DVD players. Use the function to estimate the number of DVD players the store will sell in $2018$ (correct to the nearest whole number).