57
Long division by a three-digit number (continued)
Textbook: Part 2, lesson 57, pp. 57–59
GoalMore division by a three-digit number: two-digit quotients and remainders.
New words
quotient · bo‘linmaremainder · qoldiqrounding · yaxlitlashper day · kunlik
Explanation
Let us do 13 746 : 237. 1 374 : 237: treating 237 as 200, 1 374 : 200 ≈ 6; 6 × 237 = 1 422 is too big, 5 × 237 = 1 185 fits (remainder 189). Bring down 6: 1 896 : 237 = 8. The quotient is 58. With a remainder: 4 000 : 375 = 10 (remainder 250), since 375 × 10 = 3 750.
Worked examples
13 746 : 237 = 58. Check: 237 × 58 = 13 746.
4 000 : 375 = 10 (remainder 250), since 375 × 10 = 3 750 and 4 000 − 3 750 = 250.
Class activity
“Too big or too small?”: the teacher says a guess for the quotient. Children multiply to test and say “too big”, “too small” or “right”.
Practice
1
8 160 : 340 = ?
24
2
18 018 : 286 = ?
63
3
6 500 : 480 = ? (with a remainder)
13 remainder 260
4
A mine produced 73 000 t of coal in a year (365 days). If the same amount was mined each day, how many tonnes per day?
200