This morning, we had an interesting Olympiad math class. "Ding ..." The teacher came into the classroom with a big smile on her face. The classroom suddenly became quiet. The teacher said to us, "Let me test you a question first: the quotient obtained by dividing two integers is 12, the remainder is 26, and the sum of dividend, divisor and quotient remainder is equal to 454. What is the divisor? " I read it again, two ... "... after I got the question, I thought: How can I find the divisor of this question without any divisor? But recalling that teachers often say that drawing line segments is a magic weapon to solve application problems. Why don't I try? So, I began to draw: first take the divisor as a multiple, the dividend is 26 times more than the divisor, and then draw the quotient and the remainder. Oh, it turned out to be a matter of doubling. The formula is: (454-12-26) ÷ (12+1) = 390 ÷13 = 30.
I think: we have learned the method of calculating with X. Let me write out the formula of the text first. Divider × quotient+remainder+divisor+quotient+remainder =454, then let the divisor be X, and the formula is: x×12+26+x+12+26 = 454. I subtract 12 and 26 first, then I leave the dividend and divisor, and then because there is a remainder in the dividend. I want to subtract 26, so the dividend is equal to 12. The divisor is 30. Expressed by the formula, it is: x×12+26+x+26+12 = 454.
x =(454— 12—26—26)÷( 12+ 1)
X=390÷30
X = 30。
I finished both methods at one go. Everyone gave me a approving look.
My heart is full of joy. This course is really interesting.