Why isn't the answer to TMUA-P1X-MSTAT-04 shown upfront?

The options are lettered without marking the correct one so you attempt TMUA-P1X-MSTAT-04 first — TMUA questions reward spotting the trap before you check the worked solution below.

Do I need a calculator for TMUA-P1X-MSTAT-04?

No — calculators are banned in the TMUA. TMUA-P1X-MSTAT-04 is set for a no-calculator target of about 180 seconds; the worked solution shows the fastest by-hand route.

Which TMUA specification point is TMUA-P1X-MSTAT-04?

TMUA-P1X-MSTAT-04 is Paper P1 · Statistics and probability (specification code M-Stat), level 2. Drill more of the same topic from this page.

TMUA-P1X-MSTAT-04 — Paper P1 · Statistics and probability · Level 2

P1M-StatLevel 2~180s target

Spec: M-Stat · No calculator · ~180s

The probability it rains on any given day is

0.4

, independently. What is the probability it rains on exactly one of Saturday and Sunday?

Options

$0.24$
$0.48$
$0.16$
$0.8$
$0.36$

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: tree-probability, halving-trap. Name the trap first, work the stem by hand, then open the solution below.

Show solution

P(rain then dry or dry then rain)

= 2 \times 0.4 \times 0.6 = 0.48

. Trap:

0.24

computes one ordering only — plausible if you forget the two orders (Saturday-rain and Sunday-rain).

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Same topic · same level

P1M-StatLevel 2

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Two fair six-sided dice are rolled. What is the probability that the total is 9?

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Open TMUA-P1-MSTAT-001 →

Same trap: halving-trap

P1MM3Level 2

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O is the centre of a circle and A, B lie on the circle with angle AOB = 100^°. What is angle OAB?

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Open TMUA-P1-MM3-008 →

Step up a level

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TMUA-P1X-MSTAT-04 — Paper P1 · Statistics and probability · Level 2

Options

Keep practising

Master Statistics and probability

TMUA-P1X-MSTAT-04 — Paper P1 · Statistics and probability · Level 2

Options

Keep practising

Master Statistics and probability