Understanding Divisibility

Today, we are going to explore the idea of divisibility. When we say a number is divisible by another number, it means that when you divide them, there is no remainder left over. This is super important in maths! Let’s focus on how to know if a number is divisible by 25, 50, and 100.

Divisibility by 25

Key Rule: A number is divisible by 25 if it ends in 00, 25, 50, or 75.

Examples:

  • 100 ends in 00 (Divisible)
  • 125 ends in 25 (Divisible)
  • 150 ends in 50 (Divisible)
  • 175 ends in 75 (Divisible)
  • 23 does not end in any of these (Not Divisible)

Tip: Just look at the last two digits! If they are 00, 25, 50, or 75, the number is divisible by 25.

Divisibility by 50

Key Rule: A number is divisible by 50 if it ends in 00 or 50.

Examples:

  • 200 ends in 00 (Divisible)
  • 250 ends in 50 (Divisible)
  • 350 ends in 50 (Divisible)
  • 410 does not end in either (Not Divisible)

Tip: Check only the last two digits! If they are 00 or 50, you’re good to go!

Divisibility by 100

Key Rule: A number is divisible by 100 if it ends in 00.

Examples:

  • 300 ends in 00 (Divisible)
  • 400 ends in 00 (Divisible)
  • 500 ends in 00 (Divisible)
  • 75 does not end in 00 (Not Divisible)

Tip: Just look at the last two digits. If they are 00, the number is divisible by 100!

Summary of Key Rules

  • 25: Ends in 00, 25, 50, or 75.
  • 50: Ends in 00 or 50.
  • 100: Ends in 00.

Questions for Practice

Now, let’s see how well you understand these rules. Here are some questions for you to try!

Easy Level Questions

  1. Is 100 divisible by 25?
  2. Is 150 divisible by 50?
  3. Is 200 divisible by 100?
  4. Is 75 divisible by 25?
  5. Is 300 divisible by 50?
  6. Is 50 divisible by 25?
  7. Is 125 divisible by 25?
  8. Is 450 divisible by 100?
  9. Is 500 divisible by 50?
  10. Is 550 divisible by 25?

Medium Level Questions

  1. Is 225 divisible by 25?
  2. Is 700 divisible by 50?
  3. Is 800 divisible by 100?
  4. Is 375 divisible by 25?
  5. Is 650 divisible by 50?
  6. Is 925 divisible by 25?
  7. Is 950 divisible by 100?
  8. Is 1200 divisible by 50?
  9. Is 1800 divisible by 100?
  10. Is 1450 divisible by 25?

Hard Level Questions

  1. Is 3125 divisible by 25?
  2. Is 2750 divisible by 50?
  3. Is 4500 divisible by 100?
  4. Is 9875 divisible by 25?
  5. Is 1450 divisible by 50?
  6. Is 3700 divisible by 100?
  7. Is 2150 divisible by 50?
  8. Is 8250 divisible by 25?
  9. Is 19200 divisible by 100?
  10. Is 5100 divisible by 50?

Answers

Easy Level Answers

  1. Yes (100 ÷ 25 = 4)
  2. Yes (150 ÷ 50 = 3)
  3. Yes (200 ÷ 100 = 2)
  4. Yes (75 ÷ 25 = 3)
  5. Yes (300 ÷ 50 = 6)
  6. Yes (50 ÷ 25 = 2)
  7. Yes (125 ÷ 25 = 5)
  8. Yes (450 ÷ 100 = 4.5)
  9. Yes (500 ÷ 50 = 10)
  10. Yes (550 ÷ 25 = 22)

Medium Level Answers

  1. Yes (225 ÷ 25 = 9)
  2. Yes (700 ÷ 50 = 14)
  3. Yes (800 ÷ 100 = 8)
  4. Yes (375 ÷ 25 = 15)
  5. Yes (650 ÷ 50 = 13)
  6. Yes (925 ÷ 25 = 37)
  7. Yes (950 ÷ 100 = 9.5)
  8. Yes (1200 ÷ 50 = 24)
  9. Yes (1800 ÷ 100 = 18)
  10. Yes (1450 ÷ 25 = 58)

Hard Level Answers

  1. Yes (3125 ÷ 25 = 125)
  2. Yes (2750 ÷ 50 = 55)
  3. Yes (4500 ÷ 100 = 45)
  4. Yes (9875 ÷ 25 = 395)
  5. Yes (1450 ÷ 50 = 29)
  6. Yes (3700 ÷ 100 = 37)
  7. Yes (2150 ÷ 50 = 43)
  8. Yes (8250 ÷ 25 = 330)
  9. Yes (19200 ÷ 100 = 192)
  10. Yes (5100 ÷ 50 = 102)

Conclusion

Great job practicing! Remember, just check the last two digits of a number to see if it’s divisible by 25, 50, or 100. Keep working on these concepts, and you’ll be a divisibility expert in no time!