There are strict regulations on the quality of football used in formal football match, and the standard quality is 400g. The following are the quality test results of five football (use positive numbers to record the grams that exceed the specified quality, use negative numbers to record the grams that are less than the specified quality): - 25, + 10, - 20, + 30, + 15. (1) write down the quality of each football; (2) please point out which football has better quality, and use the absolute value We can judge by our knowledge | Math enthusiast | Mathematical art

There are strict regulations on the quality of football used in formal football match, and the standard quality is 400g. The following are the quality test results of five football (use positive numbers to record the grams that exceed the specified quality, use negative numbers to record the grams that are less than the specified quality): - 25, + 10, - 20, + 30, + 15. (1) write down the quality of each football; (2) please point out which football has better quality, and use the absolute value We can judge by our knowledge

(1) The quality of each football is: 400-25 = 375 g, 400 + 10 = 410 g, 400-20 = 380 g, 400 + 30 = 430 g, 400 + 15 = 415 g. (2) the quality of football with 410 g (i.e. more than + 10 g) is better, because it is closest to the standard quality of 400 G

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