Math problem solving! The expert will answer the following question. I am in sixth grade, so I hope that the expert passing by can use elementary school knowledge to answer the question. Sorry for th

Math problem solving! The expert will answer the following question. I am in sixth grade, so I hope that the expert passing by can use elementary school knowledge to answer the question. Sorry for the trouble!

Three people donated 405 yuan. Xiaobing donated 30 yuan less than Xiaohua. Xiaobing’s donation = Xiaohua’s donation-30 yuan. Xiaorun donated more than Xiaohua. 3 yuan, Xiaorun’s donation = Xiaohua’s donation + 3 yuan, Xiaobing’s donation + Xiaohua’s donation + Xiaorun’s donation = Xiaohua’s donation – 30 yuan + Xiaohua’s donation + Xiaohua’s donation + 3 Yuan = 405 yuan. You can first ask how many Yuan Xiaohua donated and then ask how much other people donated.

Explanation: Suppose Xiaohua donated x yuan.

x-3x+x+3=405

x-3x+x+3+30-3=405+30-3

x+x+x=432

3x=432

x=144

Xiaobing: 144-30=114 (yuan)

Xiaorun: 144+3=147 (yuan) or 405-144-114=147 (yuan)

Answer: Xiaobing donated 114 yuan, Xiaohua donated 144 yuan, Xiaorun Donated 147 yuan.

Idea: The master and apprentice process at the same time for 5 hours. The master processes six more parts per hour than the apprentice. In 5 hours, he processes 30 more parts. The apprentice completes the task by processing 90 more parts. The master processes 30 more parts. You only need to complete 60 more, which is exactly one-twelfth of the task, so that you can find the equivalence relationship.

Solution: Suppose the master *** processes x pieces.

90-5*6=1/12x

60=1/12x

60*12=1/12x*12

x=720

Answer: Master *** completed 720.

Note: "*" represents the multiplication sign, and "/" represents the division sign or fraction line.

Experience: The arithmetic solution is actually a deformation of the equation. Personally, I still like to use the arithmetic solution to solve this kind of problems. If you find the equation troublesome, you can learn the arithmetic solution. I will no longer use the arithmetic method for you. Got it, if the solution is wrong, please point it out.