IB Maths AI SL 1.2 Arithmetic sequences and series Question Bank

Practise IB Maths AI SL 1.2 through questions on arithmetic terms, common differences, finite sums and applied models such as fees, savings and repeated change.

Exam points

Form an arithmetic nth-term model from SL data and identify the first term and common difference.
Use finite-sum formulae to solve SL totals, threshold and repeated-change questions in context.
Check arithmetic answers against the index, units and stated real-world interpretation.

[Maximum number: 5]

A marathon is a race over a distance of 42.19 km .

(a)

Find the week during which Rolando runs 42 km .

[ 3 ]

METHOD 1 attempt to substitute into arithmetic sequence formula
$42=6+(n-1) \times 2$ OR 42=2 n+4
( n= ) 19

METHOD 2
list of any consecutive terms ending on/above 42
at least two correct terms (not including 6, 8 and 10)
( n= ) 19

(b)

Find the total distance that Rolando runs in the first 10 weeks.

Davi runs 3 km in the first week. In each subsequent week he runs 20 % further than the previous week. These distances form the terms of a geometric sequence.

[ 2 ]

METHOD 1
$\left(S_{10}=\right) \frac{10}{2}(2 \times 6+(10-1) 2)$ $150(\mathrm{~km})$

METHOD 2
summing (some) correct terms up to 24 OR list of correct cumulative values $6+8+10+\ldots+24$ OR $6,14,24,36 \ldots$ $150(\mathrm{~km})$

All question bank results loaded

SL 1.2—Arithmetic sequences and series question 1

Question (a)

Question (b)