Page 37 - Math Skill - 5
P. 37
The Four Fundamental Operations 35
Absorbing Facts
The form of the Obelus as a horizontal line with a dot above and a dot below ‘ ÷ ’ was first used as a symbol
for division by the swiss mathematician Johann Rohn is his book Teutsche Algebra in 1659.
Fact-o-meter
Division by a 2-digit divisor In division,
Dividend > Divisor
Example: Divide 74568 by 28.
Solution: 2 6 6 3 Working
28 7 4 5 6 8 28 × 2 = 56 < 74; 2 in the thousands place of quotient
– 5 6 28 × 6 = 168 < 185; 6 in the hundreds place of quotient
1 8 5 28 × 6 = 168 < 176; 6 in the tens place of quotient
– 1 6 8
1 7 6 28 × 3 = 84 < 88, 3 in the ones place of quotient
– 1 6 8 4 is the remainder.
8 8 Verification:
– 8 4
4 Remainder Dividend = Divisor × Quotient + Remainder
= 28 × 2663 + 4 = 74564 + 4 = 74568
Division by a 3-digit Divisor
Example: Divide 624508 by 368. Working
Solution: 1 6 9 7 368 × 1 = 368 < 624: 1 in the thousands place
368 6 2 4 5 0 8 368 × 6 = 2208 < 2565; 6 in the hundreds place
– 3 6 8
2 5 6 5 368 × 9 = 3312 < 3570: 9 in the tens place
– 2 2 0 8 368 × 7 = 2576 < 2588; 7 in the ones place
3 5 7 0
– 3 3 1 2 12 is the remainder.
2 5 8 8 Verification
– 2 5 7 6 Verification = Divisor × Quotient + Remainder
1 2 Remainder
= 368 × 1697 + 12 = 624508
Properties of Division
If a number is divided by 1, the quotient is the number itself.
For example, 5190 ÷ 1 = 5190
If a number is divided by itself, the quotient is always 1 (except when 0 is divided by 0).
For example, 3430 ÷ 3430 = 1.
Division of a number by ‘0’ is not possible.
For example, 315 ÷ 0 (meaningless)
Division of zero by a number (other than zero) is zero.
For example, 0 ÷ 4 = 0; 0 ÷ 157 = 0.
