43
Division with a remainder
Textbook: Part 2, lesson 43, pp. 13–15
GoalThe algorithm for division with a remainder and checking it with multiplication.
New words
algorithm · algoritmchecking · tekshirishmultiple · karrali sonincomplete quotient · to‘liqsiz bo‘linma
Explanation
Let us do 38 : 7. 1) Find the largest number not above 38 that 7 divides: 35. 2) 35 : 7 = 5, the quotient. 3) The remainder is 38 − 35 = 3. Answer: 38 : 7 = 5 (remainder 3). Check: multiply the divisor by the quotient and add the remainder: 7 × 5 + 3 = 38.
Worked examples
50 : 6: the largest multiple of 6 not above 50 is 48, 48 : 6 = 8, remainder 50 − 48 = 2. Answer: 8 (remainder 2).
Check: 6 × 8 + 2 = 48 + 2 = 50.
Class activity
“Nearest multiple”: the teacher gives two numbers (for example 43 and 6). Children name the largest multiple of 6 not above 43 (42) and then the remainder.
Practice
1
43 : 6 = ? (with a remainder)
7 remainder 1
2
65 : 7 = ? (with a remainder)
9 remainder 2
3
29 : 4 = 7 (remainder 1). Check: 4 × 7 + 1 = ?
29
4
A craftsman has 58 nails. One shelf needs 9 nails. How many whole shelves can he make and how many nails are left?
6 remainder 4