Question
35. A mathematics teacher of primary class gave the following problem to her students to solve:
“How many classrooms of 28 students will be required for a school of 616 students?”
A student solved the problem as follows:
$1~Class=28$ Pupil
$10rightarrow2~8~0$
$10\rightarrowunderline{2~80}$
560
$2\rightarrow\frac{56}{underline{616}}$
$rightarrow10+10+2=22$ Classes
Which of the following is most appropriate for the algorithm used by the student?
(1) The student has used both the distributive and associative rules of division to solve the problem.
(2) The student has used a wrong algorithm to solve the problem.
(3) The student has used the associative rule of division over addition to solve the problem.
(4) The student has used the distributive rule of division over addition to solve the problem.
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कारण: The student has broken down 616 to divide by 28 as 280 + 280 + 56 (i.e., 28×10 + 28×10 + 28×2). This is a practical application of the distributive rule of division over addition ($a div b + c div b = (a+c) div b$), where 616 has been divided into multiples of 28.