Question

Answer all the questions

Tau decides to save money in the following ways:
He saves $ 1 in the first week $1.20 in the second week, $1.40 in the third week, and so on.
1) How much would he save in the nth week?

Answer 1

1.00 + [(n - 1) × 0.20]

or

0.80 + [n × 0.20]

Explanation:

week 1: 1.00

week 2: 1.20

week 3: 1.40

we could rewrite this as:

week 1: 1.00 + [0 × 0.20]

week 2: 1.00 + [1 × 0.20]

week 3: 1.00 + [2 × 0.20]

we can write this overall as:

week __ : 1.00 + [x × 0.20]

> x being the amount of weeks that have passed since week 1

but, we need to express this as in terms of nth, so, we need to figure out how the week is related to the x value

each week, we subtract 1 from the week number [to account for week 1]

so, we can write this as: 1.00 + [(n - 1) × 0.20]

or, we can backtrack from the first week, and start our counting at 0.80:

0.80 + [n × 0.20]

we can test this out:

(week 1)

1.00 + [(n - 1) × 0.20]

1.00 + [(1 - 1) × 0.20]

1.00 + [0 × 0.20]

1.00

or...

(week 1)

0.80 + [n × 0.20]

0.80 + [1 × 0.20]

0.80 + 0.20

= 1.00

So, nth week should be expressed as either:

1.00 + [(n - 1) × 0.20] or

0.80 + [n × 0.20]

(the second one is a little bit more simplified, but it depends on how you're supposed to write it)

hope this helps!!