Why isn't the answer to TMUA-P1-MNUM-009 shown upfront?

The options are lettered without marking the correct one so you attempt TMUA-P1-MNUM-009 first — TMUA questions reward spotting the trap before you check the worked solution below.

Do I need a calculator for TMUA-P1-MNUM-009?

No — calculators are banned in the TMUA. TMUA-P1-MNUM-009 is set for a no-calculator target of about 210 seconds; the worked solution shows the fastest by-hand route.

Which TMUA specification point is TMUA-P1-MNUM-009?

TMUA-P1-MNUM-009 is Paper P1 · Number (specification code M-Num), level 2. Drill more of the same topic from this page.

TMUA-P1-MNUM-009 — Paper P1 · Number · Level 2

P1M-NumLevel 2~210s target

Spec: M-Num · No calculator · ~210s

Two solid toy bricks are mathematically similar. The smaller has length

5

cm and mass

300

g; the larger has length

10

cm. What is the mass of the larger brick?

Options

$600$ g
$900$ g
$1200$ g
$2400$ g
$4800$ g

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: similarity-powers, area-volume-confusion. Name the trap first, work the stem by hand, then open the solution below.

Show solution

Doubling all lengths scales volume (hence mass) by

2^3 = 8

300 \times 8 = 2400

g. Trap:

1200

g uses the square law (

\times 4

) for areas — plausible if you confuse area and volume scaling.

Keep practising

Same topic · same level
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Same trap: similarity-powers
P1M-GeoLevel 3
TMUA-P1-MGEO-016
Two cones are mathematically similar with heights 3 cm and 9 cm. The smaller cone has volume 20 cm ^3. What is the volum…
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Step up a level
P1M-NumLevel 3
TMUA-P1-MNUM-011
4000 is invested. It grows by 5\% in year one, then falls by 5\% in year two. What is its final value?
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Open TMUA-P1-MNUM-011 →

Browse more

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Keep practising

Same topic · same level

P1M-NumLevel 2

TMUA-P1-MNUM-005

What is the lowest common multiple (LCM) of 12, 18 and 20?

Number

Open TMUA-P1-MNUM-005 →

Same trap: similarity-powers

P1M-GeoLevel 3

TMUA-P1-MGEO-016

Two cones are mathematically similar with heights 3 cm and 9 cm. The smaller cone has volume 20 cm ^3. What is the volum…

Geometry

Open TMUA-P1-MGEO-016 →

Step up a level

P1M-NumLevel 3

TMUA-P1-MNUM-011

4000 is invested. It grows by 5\% in year one, then falls by 5\% in year two. What is its final value?

Number

Open TMUA-P1-MNUM-011 →

TMUA-P1-MNUM-009 — Paper P1 · Number · Level 2

Options

Keep practising

Master Number

TMUA-P1-MNUM-009 — Paper P1 · Number · Level 2

Options

Keep practising

Master Number