Difficult!No one in the class did it right?
It's a 3rd grade math problem, and you can do it in 2nd grade!But in a certain class in the third grade, no one did it right!The teacher was very angry and threw down the sentence "Won't addition be, won't division either?""A few students suddenly realized!
Title, as shown in Figure 1.
Analysis 1: Applicable to the second grade!
Single digits: From c+c+c=8 or c+c+c=10+8 or c+c+c=20+8, c=6, that is, the sum of the single digits into 1.
Hundred: From a+a+a=8 or a+a+a+1=8 or a+a+a+2=8, a=2 can be obtained, and the sum of ten digits is 2.
Ten digits: b+b+b+1=20+8 from and so b=9. Therefore a+b+c=17.
Analysis 2: Applicable to the third grade!
The vertical addition of Figure 1 is rewritten as: a three-digit number satisfies abc+abc+abc=888, and finds a+b+c=?
abc=888 3=296, so a=2, b=9, c=6, a+b+c=17.
Note 1: Only in the third grade can the division of multiple digits by one digit be learned, so the second grade is not applicable to the second grade.
Note 2: The addition vertical style can deceive people!It is easy to mislead students to insist on using only addition to solve the problem, which increases the difficulty of the solution. This is probably the reason why the teacher is angry: no student thinks of solving it by division!
If you have any ideas or methods, please leave a message to share!