(1) The weight of Xiao Dong and Xiao Jun is 32× 2 = 64 kg.
The weight of Obana Xiaojun is: 28× 2 = 56 kg.
The weight of Xiaodong and Xiaohua is 30× 2 = 60 kg.
The weights of Xiaodong, Xiaojun and Xiaohua are: (64+56+60) ÷ 2 = 90kg.
The average weight of these three students is: 90 ÷ 3 = 30 kg.
(2) Xiao Dong's weight: 90-56 = 34kg.
Small unit weight: 90-60 = 30 kg
Small flower weight: 90-64 = 26kg.
123456789 Nine numbers, one number in each bracket makes the formula valid (each number cannot be reused).
The first question:
( )( )+( )-( )=( )
( )*( )=( )( )
The second question:
( )( )( )( )*( )=( )( )( )( )
The first question: (1) (3)+(2)-(7) = (8)
⑹*⑼=⑸⑷
Question 2: (1) (7) (3) (8) * (4) = (6) (3) (6)
Or: (1) (9) (3) * (4) = (8) (5) (2)
Wang Ran runs along a 60-meter-long rectangle for 6 minutes, running 120 meters per minute to find the width.
A * * * ran away:
120 * 60 = 720m
720\60= 12 (m)
That's all. what do you think?