The arithmetic sequence 5, 9, 13, continues. What is its 20th term?

Worked solution for TMUA-P1-MM2-002 is revealed on this page behind the solution details.

Why isn't the answer to TMUA-P1-MM2-002 shown upfront?

The options are lettered without marking the correct one so you attempt TMUA-P1-MM2-002 first — TMUA questions reward spotting the trap before you check the worked solution below.

Do I need a calculator for TMUA-P1-MM2-002?

No — calculators are banned in the TMUA. TMUA-P1-MM2-002 is set for a no-calculator target of about 150 seconds; the worked solution shows the fastest by-hand route.

Which TMUA specification point is TMUA-P1-MM2-002?

TMUA-P1-MM2-002 is Paper P1 · Sequences and series (specification code MM2), level 1. Drill more of the same topic from this page.

TMUA-P1-MM2-002 — Paper P1 · Sequences and series · Level 1

P1MM2Level 1~150s target

Spec: MM2 · No calculator · ~150s

The arithmetic sequence

5, 9, 13, \dots

continues. What is its 20th term?

Options

$77$
$81$
$85$
$89$
$80$

Letters only — the answer key is hidden. Work it out, then check the solution below.

Hint (check trope)

No written hint yet — check the trope: arithmetic-nth-term. Name the trap first, work the stem by hand, then open the solution below.

Show solution

The common difference is

4

, so the 20th term is

5 + 19 \times 4 = 81

Keep practising

Same topic · same level
P1MM2Level 1
TMUA-P1-MM2-001
Let f(x) = 2x + 3 and g(x) = x^2. What is the value of f(g(2))?
Sequences and series
Open TMUA-P1-MM2-001 →
Step up a level
P1MM2Level 2
TMUA-P1-MM2-006
A sequence is defined by u_1 = 5 and u_n+1 = 2u_n - 3. What is the value of u_3?
Sequences and series
Open TMUA-P1-MM2-006 →
More in this topic
P1MM2Level 1
TMUA-P1-MM2-003
What is the value of 1 + 2 + 3 + + 50?
Sequences and series
Open TMUA-P1-MM2-003 →

Browse more

Loading…

Keep practising

Same topic · same level

P1MM2Level 1

TMUA-P1-MM2-001

Let f(x) = 2x + 3 and g(x) = x^2. What is the value of f(g(2))?

Sequences and series

Open TMUA-P1-MM2-001 →

Step up a level

P1MM2Level 2

TMUA-P1-MM2-006

A sequence is defined by u_1 = 5 and u_n+1 = 2u_n - 3. What is the value of u_3?

Sequences and series

Open TMUA-P1-MM2-006 →

TMUA-P1-MM2-002 — Paper P1 · Sequences and series · Level 1

Options

Keep practising

Master Sequences and series

TMUA-P1-MM2-002 — Paper P1 · Sequences and series · Level 1

Options

Keep practising

Master Sequences and series