Divide 4 digit number by 2 digit number resulting in decimal answer
Using things we know
Just like dividing numbers in the hundreds that result in a decimal answer, we have strategies that can help us multiply larger numbers as well. The first video uses two strategies to solve $2750\div20$2750÷20. First, we solve $2750\div10$2750÷10, and then we can take half of our answer, using partitioning to solve the rest of our problem, breaking it into smaller problems.
Let's take a look at how we do this.
How many groups of?
We can also partition our number, and find out how many groups of our divisor we have. If we are dividing by $25$25, we can look at our thousands and hundreds, and find out how many groups of $25$25 we have. This then helps us solve our division problem, with any remainder left at the end, which we change to decimals. Video 2 shows you how we can take this approach.
Short division
Finally, we solve $2750\div20$2750÷20 again, but this time using short division. By remembering place value, we can divide each digit, working from left to right. Instead of thinking we can't share any further, we move from units to tenths, and find we can!
Expressing your remainder as a fraction often allows you to find the equivalent fraction in tenths or hundredths, which makes it easier to write your final answer as a decimal.
Many of the tips and tricks you have seen before can be used in division problems, such as partitioning and regrouping, even your normal times tables!
Examples
Question 1
We want to find $9385\div25$9385÷25.
Choose the most reasonable estimate for $9385\div25$9385÷25.
Between $300$300 and $400$400.
AGreater than $500$500.
BLess than $200$200.
CBetween $30$30 and $40$40.
DFill in the multiplication table for $25$25.
$1$1 $25$25 $2$2 $\editable{}$ $3$3 $\editable{}$ $4$4 $\editable{}$ $5$5 $125$125 $6$6 $\editable{}$ $7$7 $175$175 $8$8 $\editable{}$ $9$9 $\editable{}$ $10$10 $\editable{}$ Complete the short division to find $9385\div25$9385÷25.
$\editable{}$ $\editable{}$ $\editable{}$ $.$. $\editable{}$ $25$25 $9$9 $3$3 $\editable{}$ $8$8 $\editable{}$ $5$5 $.$. $\editable{}$ $\editable{}$
QUESTION 2
We want to find $1023\div22$1023÷22.
Choose the most reasonable estimate for $1023\div22$1023÷22.
Less than $30$30.
ABetween $400$400 and $500$500.
BBetween $40$40 and $50$50.
CGreater than $600$600.
DFill in the multiplication table for $22$22.
$1$1 $22$22 $2$2 $\editable{}$ $3$3 $\editable{}$ $4$4 $\editable{}$ $5$5 $110$110 $6$6 $\editable{}$ $7$7 $\editable{}$ $8$8 $\editable{}$ $9$9 $198$198 $10$10 $\editable{}$ Complete the short division to find $1023\div22$1023÷22.
$\editable{}$ $\editable{}$ $.$. $\editable{}$ $22$22 $1$1 $0$0 $2$2 $\editable{}$ $3$3 $.$. $\editable{}$ $\editable{}$
QUESTION 3
We want to find $7752\div32$7752÷32.
Choose the most reasonable estimate for $7752\div32$7752÷32.
Between $200$200 and $300$300.
ALess than $100$100.
BGreater than $400$400.
CBetween $20$20 and $30$30.
DFill in the multiplication table for $32$32.
$1$1 $32$32 $2$2 $\editable{}$ $3$3 $\editable{}$ $4$4 $\editable{}$ $5$5 $160$160 $6$6 $\editable{}$ $7$7 $\editable{}$ $8$8 $256$256 $9$9 $\editable{}$ $10$10 $\editable{}$ Complete the short division to find $7752\div32$7752÷32.
$\editable{}$ $\editable{}$ $\editable{}$ $.$. $\editable{}$ $\editable{}$ $32$32 $7$7 $7$7 $\editable{}$ $5$5 $\editable{}$ $2$2 $.$. $\editable{}$ $\editable{}$ $\editable{}$ $\editable{}$