A diving vessel descends below the surface of the water at a constant rate so that the depth of the vessel after $1$1 minute, $2$2 minutes and $3$3 minutes is $50$50 metres, $100$100 metres and $150$150 metres respectively.
By how much is the depth increasing each minute?
What will the depth of the vessel be after $4$4 minutes?
Continuing at this rate, what will be the depth of the vessel after $10$10 minutes?
A paver needs to pave a floor with an area of $800$800 square metres. He can pave $50$50 square metres a day.
For a fibre-optic cable service, Christa pays a one off amount of $\$200$$200 for installation costs and then a monthly fee of $\$30$$30.
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.