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I want to ask how to do some math problems. Please help me quickly.
1. If Zhao wins the gold medal, then Li is wrong.

(Note: If Xiao Li wins the silver medal or bronze medal, it will be regarded as {Xiao Li can't win the gold medal}. This statement is correct. It is considered a mistake that only Xiao Li won the gold medal. )

If so, there will be two gold medals, so they are all contradictory.

(Wrong: Xiao Zhao won the gold medal); (right: small can't get the gold medal); (Wrong: I can't win the bronze medal)

Look at the third sentence first (wrong: Xiao can't win the bronze medal) (meaning Xiao Liu will definitely win the bronze medal)

Because if Liu wins a gold medal or a silver medal, people think he won't win a bronze medal, so this sentence becomes correct.

Please look at the second sentence (right: Xiao can't get the gold medal), which means that Xiao Li will never get the gold medal, because this sentence is right, Xiao Liu won the bronze medal (so small only won the silver medal)

Naturally, the gold medal will fall to Xiao Zhao.

However, it was wrong for Xiao Zhao to win the gold medal ... (Error: Xiao Zhao won the gold medal).

(Wrong: Xiao Zhao won the gold medal); (wrong: small can't get the gold medal); (Right: Xiao didn't win the bronze medal)

I believe everyone will understand when they see this.

Look at the second sentence first (wrong: Xiao didn't win the gold medal), which means Xiao Li won the gold medal.

Look at the third sentence (right: Xiao can't win the bronze medal) and the gold medal was taken away by Xiao Li ... then Xiao only won the remaining silver medal.

Finally, look back at the first sentence (Wrong: Xiao Zhao won the gold medal). Zhao failed to win the gold medal, but he won the silver medal ... so he must win the bronze medal.

Only in this way can it go smoothly.

2. Analysis: First, get the total score of 26 people, and set the number of people who get 3 points and the number of people who get 5 points. The relationship is 3× the number of people who get 3 points +4× the number of people who get 4 points +5× the total score of 26 people, and then substitute the relevant values into integer values. Solution: The total score of 26 people is 26 × 4.8 = 10.

∴ Total score of 26 people 125 points;

The number of people who get 3 points is X, and the number of people who get 5 points is Y.

Then 3x+3x4+5y = 125.

3x+5y= 1 13,

The integer solution is x= 1 and y = 22.

So the answer is 22.

3. Analysis: Let A be the distance you walked for the first time on the first day, B be the distance you walked every day since the second day, and X be the number of days. Then according to the meaning of the question, the equation 15A = X (A+9B) is listed. Then the equation15a = a+(a+b)+(a+2b)+(a+3b)+(a+4b)+(a+5b)+(a+6b)+(a+7b)+(a+8b)+(a+). Solution: Solution: Let A be the distance you walk for the first time on the first day, B be the distance you walk every day from the second day, and X be the number of days you want.

15a = a+(a+b)+(a+2b)+(a+3b)+(a+4b)+(a+5b)+(a+6b)+(a+7b)+(a+8b)+(a+9b)= 10a+45b,

∫ 15a = x(a+9b)

∴ 15a= 10a+45b,

∴5a=45b,

∴a=9b,

∴ 15a=x(a+a), and x=7.5 (days).

So the answer is: 7.5.

If you don't understand, you can +QQ 1046293636.