Required Mathematical Intelligence

Chapter 86 Odd and Even Numbers

In the activity class, Teacher Heixiong smiled and said to everyone: "Let's play a game, shall we?"

"Okay!" The little animals answered in unison.

"Please prepare two small notes each." Teacher Hei Xiong cleared his throat and said.

The little animals didn't know what game Mr. Black Bear wanted them to do, their eyes lit up with excitement, and soon they all prepared the little notes.

Teacher Heixiong looked around the class and said, "Please write an odd number and an even number on two small pieces of paper. After writing, hold one in each hand. Don't show it to me or the classmates around you. "

The little animals just learned about odd and even numbers not long ago, and after a while, everyone completed the request made by Mr. Black Bear.

"Listen," Teacher Heixiong said clearly, "all of you, please multiply the number in your right hand by 2, the number in your left hand by 3, and add the products together. Don't make a sound."

After the small animals have been counted one by one, Mr. Hei Xiong asked the small animals whose numbers were odd to line up, and those who got even numbers to line up.

The little animals all stood up, looking at Mr. Black Bear with interest, wondering what he wanted them to do next.

"Okay!" Teacher Heixiong pointed to the row of small animals with odd numbers and said, "The ones in your left hand are all odd numbers."

It pointed to another row of small animals and said, "The ones you hold in your left hand are all even numbers."

The two rows of small animals spread out their palms to see, no, Teacher Heixiong guessed completely correctly.

The little animals were so surprised that they couldn't help asking, "Teacher, how did you know?"

[Answer: odd number × 2 = even number odd number × 3 = odd number
Even × 2 = Even Even × 3 = Even
And even tens even = even even tens odd = odd
When the left hand is an odd number, the odd number × 3 is an odd number, and the odd number is an even number (the even number in the right hand × 2), and the result is an odd number.

And if the right hand is an odd number, the odd number × 2 becomes an even number, and the even number becomes an even number (the even number in the left hand × 3), and the result is an even number.

This is the reason why the final result is the same as the parity of the number in the left hand, which is the basis of my guess.

The little animals suddenly realized...]
(End of this chapter)