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Themed maths

Summer maths escape room for CBSE Class 10

The beach hut is locked, and the keys are in a box with six locks. Teams solve six locks in order; each code is needed for the next. Printable clue cards, a teacher answer key and a bonus lock, all without a calculator.

Level
CBSE Class 10 (Class 9 can try most of it)
Time
41 minutes, plus a 10-minute extension
Topics
Real numbers and arithmetic progressions; Linear equations; Surface areas and volumes; Trigonometric ratios
Equipment
No calculator. Use π = 22/7 where a lock says so.

Download student sheet (PDF)Answers (PDF)

Suggested timings

PartTimeWhat
Starter5 minQuick questions on the board
Main: lock 16 minThe shells
Main: lock 26 minThe prime lock
Main: lock 36 minThe equation
Main: lock 46 minThe water tank
Main: lock 56 minThe kite
Main: lock 66 minThe beach hut
Extension10 minFast finishers or homework

Starter (5 minutes)

Warm-up before the locks: quick questions on the board.

  1. Find √196.
  2. Write down tan 45°.
  3. Work out (−3)2.

Main activity (36 minutes)

Lock 1: The shells (6 min)

Shells are collected one on day 1, two on day 2, and so on.

  1. How many shells are collected in the first 10 days? This is code 1.

Lock 2: The prime lock (6 min)

Write code 1 as a product of primes.

  1. The larger prime is code 2.

Lock 3: The equation (6 min)

The lock shows 3x − 4 = c, where c is code 2.

  1. Solve for x. This is code 3.

Lock 4: The water tank (6 min)

A cylindrical tank has radius 7 m.

  1. Its height is code 3 metres. Find its volume in m3. (Use π = 22/7.) This is code 4.

Lock 5: The kite (6 min)

The lock shows sin 30°.

  1. Work out sin 30° × code 4 ÷ 35. This is code 5.

Lock 6: The beach hut (6 min)

The last lock.

  1. Find the term of the AP 3, 8, 13, … whose position is code 5. It opens the hut.

Extension (10 minutes)

Bonus lock for the fastest team.

  1. Find the mean of 4, 7, 9, 12 and 18.

For teachers

Teacher notes and full worked answers
  • How to run it: print the student sheet and cut out the six lock cards. Give each team lock 1. When a team brings you the right code, give them the next card (the answer key is in the answers PDF). The first team to open lock 6 escapes. Teams can also have every card at once and race through them in order.
  • Each code is used in the next lock, so check every code before the team moves on: one slip early on breaks the chain.

Starter

  1. 14
    • 14 × 14 = 196
  2. 1
    • The opposite and adjacent sides are equal.
  3. 9
    • (−3) × (−3) = 9

Lock 1: The shells

  1. 55
    • 1 + 2 + … + 10 = 10 × 11 ÷ 2 = 55

Lock 2: The prime lock

  1. 11
    • 55 = 5 × 11

Lock 3: The equation

  1. 5
    • 3x = 15
    • x = 5

Lock 4: The water tank

  1. 770
    • πr2h = 22/7 × 49 × 5 = 770

Lock 5: The kite

  1. 11
    • sin 30° = 1/2
    • 770 ÷ 2 ÷ 35 = 11

Lock 6: The beach hut

  1. 53
    • a11 = 3 + 10 × 5 = 53

Extension

  1. 10
    • 50 ÷ 5 = 10

The same answers are in the answers PDF. Every answer was recomputed by computer before publishing.

Practise the topics

Summer puzzle pack maths · Ada Lovelace Day maths · Halloween maths · All themed maths

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