Measurement

A. Saima's pencil ✓

Saima's pencil is 15 cm and Aditya's is 10 cm. Since 15 > 10, Saima's pencil is longer.

Why the others are wrong:
- B — Aditya's is actually shorter (10 cm < 15 cm)
- C — They're different lengths, so they can't be the same
- D — We have clear measurements, so we can definitely determine the answer

• Book (A) is correct — 25 cm is larger than 20 cm, so the book is wider.

• Box (B) is wrong — The box is only 20 cm, which is smaller than the book's 25 cm.

• Both are the same (C) is wrong — 20 cm and 25 cm are different measurements.

• Cannot be determined (D) is wrong — We have clear measurements for both objects, so we can easily compare them.

Correct Answer: 600 m²

To find the area of a rectangle, multiply length × width: 30 m × 20 m = 600 m².

Why the others are wrong:
- 500 m² – This would be 25 × 20, which doesn't match the given dimensions
- 400 m² – This would be 20 × 20, which ignores the full length of 30 m
- 300 m² – This would be 15 × 20, which uses only half the length

Correct answer: A (Bottle)

• The bottle is 50 cm tall and the can is 20 cm tall, so 50 cm > 20 cm—the bottle is taller.

Why the others are wrong:

• B (Can): The can is only 20 cm, which is shorter than the bottle's 50 cm.
• C (Both are the same): The heights are different numbers (50 ≠ 20), so they're not equal.
• D (Cannot be determined): We have exact measurements for both, so we can definitely compare them.

A. 200 cm — CORRECT
• 1 meter = 100 centimeters
• 2 meters = 2 × 100 = 200 cm

B. 20 cm — WRONG
• This would only be 0.2 meters, way too small.

C. 2000 cm — WRONG
• This would be 20 meters, ten times too much.

D. 20,000 cm — WRONG
• This would be 200 meters, 100 times too much.

A. 20 mm ✓

1 centimeter = 10 millimeters, so 2 centimeters = 2 × 10 = 20 mm.

Why the others are wrong:
- B (10 mm): This is only 1 centimeter, not 2.
- C (200 mm): This would be 20 centimeters (you multiplied by 100 instead of 10).
- D (2000 mm): This would be 2 meters (way too large).

Correct answer: A (3 kilometers)

• 1 kilometer = 1000 meters, so 3 kilometers = 3000 meters
• 3000 meters is greater than 2000 meters, making 3 km longer

Why others are wrong:
- B: 2000 meters is shorter (only 2 km)
- C: They're not equal; 3 km is 1000 meters longer
- D: We have all the information needed to compare them

A. 1 kg — Correct
- 1000 grams equals 1 kilogram because 1 kg = 1000 g. You divide 1000 by 1000 to convert grams to kilograms.

B. 0.5 kg — Wrong
- This would be only 500 grams, half the weight of the fruit.

C. 10 kg — Wrong
- This would be 10,000 grams, ten times too heavy.

D. 100 kg — Wrong
- This would be 100,000 grams, way too heavy for a piece of fruit.

• A is correct (150 mm): Since 1 cm = 10 mm, multiply 15 cm × 10 = 150 mm.

• B is wrong (1500 mm): This assumes 1 cm = 100 mm, which is incorrect.

• C is wrong (15,000 mm): This would be true if the pen were 150 cm long, not 15 cm.

• D is wrong (150,000 mm): This vastly overshoots—it would be the length of a 1.5 km object!

A. 1000 m — Correct
One kilometer equals 1,000 meters. The prefix "kilo-" means 1,000, so you multiply: 1 km × 1,000 = 1,000 m.

B. 10 m — Wrong
This is way too short—only 10 meters is about the length of a school bus, not a full kilometer.

C. 100 m — Wrong
100 meters is closer, but still only one-tenth of a kilometer. You'd need to walk 10 of these distances to equal 1 km.

D. 10,000 m — Wrong
This is 10 times too much. You multiplied by 10,000 instead of 1,000.