Division by One Digit Divisors What are you
Division by One Digit Divisors
What are you doing when you divide? • When you divide, you are trying to split something into equally numbered groups • Dividing these 16 apples into 4 equal groups, gives you 4 groups that have 4 apples in each of the groups: • Take these 16 apples:
Division by One-digit Divisors • Today you will learn how to divide a three-digit dividend by a one-digit divisor, to get a quotient without a remainder • Let’s review these terms
What are the parts of a division problem? • • The dividend is the number you are dividing The divisor is the number you are dividing by The quotient is the evenly divided result The remainder is what is left over that cannot be evenly divided
When we write the problem like this: 136 5 = 27 r 1 136 is the dividend 5 is the divisor 27 1 is the quotient remainder
When writing it like this: 5, the divisor, moves to here 27 r 1 1 is the remainder 5 136 27, the 136, the quotient, stays dividend, here moves here
How do you solve a division problem? • Solving a division problem is a step by step process • The method we will learn today is based the words for the people in our families. • They are: Father Mother Sister Brother
The “Family” Method Father = Find Mother = Multiply Sister = Subtract Brother = Bring Down
Father • Father stands for find • Start by looking at the first number in the dividend • Find the multiple of the divisor that comes closest to that number, without going higher • Use your knowledge of math facts, or a multiplication grid
Father = find the number closet to the first digit 3 2 711 • In the 3’s, the number closest to 7, but not more than 7, is 6 • The other factor is 2 • Put a 2 above the 7 2 6
Mother = multiply the number that is the factor that you found times the divisor • You found 2, multiply it times the divisor, 3 • 2 times 3 equals 6 2 X 3=6 • Put a 6 under the 7 3 2 711 6
Sister = subtract the number you got by multiplying the divisor, from the number in the dividend • You got a 6 when you multiplied • Subtract 6 from 7 • 7– 6=1 2 3 711 – 6 1 • The difference must be smaller than the divisor!!!
Brother = bring down the next number, from the number in the dividend • Bring down the next number in the dividend • The new number you have is 11 2 1 3 711 – 6 11 • Now start over again with Father for the ten’s
Now, let’s do the second step • Father: 9 is the closest multiple, the other factor you found is 3 • Mother: 3 X 3 = 9, put a 9 under the 11 • Sister: subtract 9 from 11 11 - 9 = 2 • Brother: bring down the 1 23 1 3 711 – 6 11 – 9 21
Now, let’s do the last step • • 2 37 Father: 21 is the closest 1 3 711 multiple, the other factor is 7 – 6 Mother: 7 X 3 = 21, put 21 under 11 the 21 – 9 Sister: subtract 21 from 21 21 21 - 21 = 0 – 21 Brother: nothing’s left, you’re done! 0
Now, let’s practice! • Father • Mother • Sister • Brother 2 6 864 4 8 – 8 06
Now, let’s do the second step • Father • Mother • Sister • Brother 21 64 4 864 – 8 06 – 4 24
Now, let’s do the last step • Father • Mother • Sister • Brother 2 16 6 4 864 – 8 06 – 4 24 – 24 0
What do I do with division now? • Finish the rest of the worksheet • Homework: probs. 1 -10, p. 64 in text • Go to this icon on the class’ computers for extra practice if you have free time • Look for the same icon on the class’ website for practice at home
- Slides: 19