Grade 3 Math - Teach You to Think Every Day

Author: Chai Changlong
Publisher:
Publish Date: 2006-08-01
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On Friday, 400 PLA soldiers conducted a formation drill, standing in 5 rows with a 2-meter interval between each pair in front and back. How long is the formation?
Tips: 400 soldiers, standing in 5 rows, the length of the formation should be calculated as 400 ÷ 5 = 80 (people). With a 2-meter interval between each pair, 80 people have 80 - 1 = 79 intervals in total. The length of the formation is 2 × 79 = 158 (meters).
400 ÷ 5 = 80
2 × (80 - 1) = 158 (meters)
Answer: The formation is 158 meters long.
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1. There are 40 athletes standing in 2 rows, with a 1-meter interval between each pair. How long is the formation?
2. Students from the school participated in a formation drill. 404 students lined up, with 4 students per row and a 5-decimeter interval between each row. How long is the entire formation?
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