Applying GCD and LCM in Real Life Situations

Try these questions

5 questions from this lesson’s quiz. Start the lesson to answer them and see the right answers.

1. 1. A carpenter has two timber beams of length 54 cm and 72 cm. He cuts both into equal pieces, each as long as possible, with no timber wasted. Which concept does he use, and what is the length of each piece?

   • A. GCD; 18 cm
   • B. LCM; 216 cm
   • C. GCD; 9 cm
   • D. LCM; 18 cm

2. 2. Two matatus leave a bus park together at 8:00 a.m. One departs every 15 minutes and the other every 20 minutes. After how many minutes will they next depart together?

   Type your answer (in minutes) in the lesson.

3. 3. A school garden has sides of 84 m and 108 m. Fence posts are placed at equal distances along both sides, with the greatest possible distance between consecutive posts. What is the distance between posts?

   Type your answer (in m) in the lesson.

4. 4. A shopkeeper has containers holding 30 litres and 45 litres. He says the LCM gives the largest can that can measure both exactly. What is the correct statement?

   • A. He is right, because the LCM is 90 litres
   • B. He is wrong; he should use the GCD, which is 15 litres
   • C. He is wrong; he should use the GCD, which is 5 litres
   • D. He is right, because the LCM is the largest number

5. 5. Two or more repeating events happening at the exact same moment, such as bells ringing together, is called what? (one word)

   Type your answer in the lesson.

More in Factors

• ▸Divisibility Tests for 3, 6, 9 and 11
• ▸Composite Numbers as a Product of Prime Factors
• ▸Greatest Common Divisor by Factor Method
• ▸Least Common Multiple by the Factor Method
• ▸Factor Games, IT Devices and Revision
• ▸Comparing and Ordering Fractions
• ▸Adding Fractions
• ▸Subtracting Fractions

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