$21$ Exercise $1$

L$15$ and L$16$ show the order fee and cost per unit for a product. Rows $18$ and

$19$ show the units purchased by month for one customer. Calculate the cost of

the units purchased for each month plus the order fee, using a formula in cell$-$

L$20$ with appropriate references to L$15,$ L$16$ and L$20$ so it will copy correctly to

T$20.$ Copy the formula across to T$20.$ Scroll right to see completed example.