Comparing Three-Digit Numbers — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. If A = 342, B = 345, and C = 324, which number is the greatest?
A) A = 342
B) B = 345
C) C = 324
D) They are all equal
All three have 3 hundreds. Tens are 4, 4, and 2, so C is out. Between 342 and 345, the ones are 2 vs 5, so B = 345 is greatest.
2. Which is the least: 507, 570, or 705?
A) 507
B) 570
C) 705
D) They are all equal
Hundreds digits are 5, 5, and 7, so 705 is out. Between 507 and 570, tens are 0 vs 7, so 507 is the least.
3. Arrange 612, 621, and 216 from least to greatest. Which one is in the middle?
A) 612
B) 621
C) 216
D) They are all equal
216 has 2 hundreds so it is least. Between 612 and 621, tens are 1 vs 2, so 621 is greatest and 612 is in the middle.
4. Which is the greatest: 489, 498, or 484?
A) 489
B) 498
C) 484
D) They are all equal
All have 4 hundreds. Tens are 8, 9, and 8. The 9 in 498 is the largest tens digit, so 498 is the greatest.
Part B: Fill in the Blank
Write the correct answer on each line.
1. Of 231, 213, and 312, the greatest is 312 .
312 has 3 hundreds while 231 and 213 have only 2 hundreds, so 312 is the greatest number.
2. Of 560, 506, and 605, the least is 506 .
Hundreds are 5, 5, and 6, so 605 is out. Between 560 and 506, the tens are 6 vs 0, so 506 is least.
3. Of 748, 784, and 847, the middle number is 784 .
847 is greatest because of 8 hundreds, and 748 is least with smaller tens, so 784 is the middle value.
4. Of 300, 299, and 301, the greatest is 301 .
300 and 301 share 3 hundreds, while 299 has 2 hundreds. Between 300 and 301, ones 1 beats 0, so 301 is greatest.
5. Of 150, 105, and 510, the least is 105 .
510 has 5 hundreds so it is biggest. Between 150 and 105, tens 5 vs 0 means 105 is least.