NZ Level 7 (NZC) Level 2 (NCEA) Applications of Arithmetic Progressions

## Interactive practice questions

A diving vessel descends below the surface of the water at a constant rate so that the depth of the vessel after $4$4 minutes, $8$8 minutes and $12$12 minutes is $5$5 metres, $10$10 metres and $15$15 metres respectively.

If $n$n is the number of minutes it takes to reach a depth of $40$40 metres, solve for $n$n.

Easy
Approx 3 minutes

Tobias starts his career with a monthly wage of $\$3500$$3500. At the beginning of each year that follows he receives a raise and his monthly wage for that year will be \160$$160 greater than the previous year.

A termite treatment will cost $\$250$$250 for the first half hour, \245$$245 for the second half hour, $\$240240 for the third half hour and so on.

What will be the cost of a treatment that takes $6$6 hours?

A paver needs to pave a floor with an area of $800$800 square metres. He can pave $50$50 square metres a day.

### Outcomes

#### M7-3

Use arithmetic and geometric sequences and series

#### 91258

Apply sequences and series in solving problems