Next week, the children will be looking at addition and subtraction. In particular, the children will be adding and subtracting numbers mentally with increasing larger numbers.
Adding in your head
- Breaking up numbers
40 + 67 is the same as
40 + 60 + 7, which is
- Rounding numbers
42 + 89 is the same as
(40 + 80) + (2 + 9), which is
120 + 11, which is 131
- Subtracting in your head
- Breaking up numbers
63 – 37 is the same as 63 – 30 – 7
63 – 30 = 33
33 – 7 = 26
- Rounding numbers
63 – 37 is the same as 63 – 40, then adding 3
63 – 40 = 23
23 + 3 = 26
- Counting on
To work out 63 – 37, count on from 37 to 63
Count on from 37 to 40 to get 3
Count on from 40 to 60 to get 20
Count on from 60 to 63 to get 3
3 + 20 + 3 = 26
You can have a go at the following games to practice adding and subtracting numbers mentally from the following website.
Next week, the children will be focusing on decimals. They will be counting up and down in thousandths; recognising that thousandths arise from dividing an object into 1000 equal parts and in dividing numbers or quantities by 1000.
When ordering numbers, we should always compare the digits on the left first.
For example, which is greater: 2.701 or 2.71?
Both numbers have two units and seven tenths, but 2.701 has no hundredths, whereas 2.71 has one hundredth. Therefore, 2.71 is greater than 2.701.Another way to look at it is to write a zero at the end of 2.71 to make it 2.710 (this does not change its value, because it is after the decimal point).The two numbers are now 2.710 and 2.701. It is quite easy to see that 2.710 is bigger (just as 2710 is bigger than 2701).
When finding 1/1000th of a number we simply divide that number by 1000.
Hello and welcome to Y5. Each week there will be maths support on the school blog to help the children prepare for the following weeks maths objectives. Next week, we will be covering place value and counting on in 100′s, 1000′s, 10,000′s and 100,000′s. To help us do this, we need to look at our place value chart.
Use place value headings to work out the value of each digit in a number.
A number is made of one or more digits. The number 683, for example, is made of the digits 6, 8 and 3. The position of a digit in a number is very important. A digit’s value depends on its position in the number.
So the number 351489.3 is three hundred and fifty-one thousand, four hundred and eighty nine, and three tenths.
Try these links below and tackle some of the games based around place value.
With it being assessment week next week, the children will be recapping a variety of objectives that they have learnt throughout the year. They will be focusing on measurements and converting between each one.
Converting between metric and imperial units
Here are some examples of metric and imperial measures of length, mass and capacity:
||mm, cm, m, km
||inch, foot, yard, mile
||mg, g, kg
||ounce (oz), pound (lb), stone
||ml, cl, l
You will be expected to know some common conversions between metric and imperial units. Some of these are shown below, but check with your teacher which ones you need to learn.
- 1 km = 5/8 mile
- 1 m = 39.37 inches
- 1 foot = 30.5 cm
- 1 inch = 2.54 cm
- 1 kg = 2.2 lb
- 1 gallon = 4.5 litres
- 1 litre = 1 3/4 pints
Next week in Maths, we will be recognising the percent symbol (%) and understand that per cent relates to ‘number of parts per hundred’ and write percentages as a fraction with denominator 100, and as a decimal.
Per cent means ‘out of 100′
The sign % stands for ‘per cent’ which means ‘out of 100′.
- 40% means 40 out of 100
- 11% means 11 out of 100
Converting between percentages and decimals
To change a percentage to a decimal, divide by 100.
Change 48% to a decimal: 48 ÷ 100 = 0.48
To change a decimal to a percentage, multiply by 100.
Change 0.67 to a percentage: 0.67 x 100 = 67%
For extra support on this area, check out the bbc website that has a fun video on decimals and percentages for the children to use.
Next week in Maths, the children will be focusing on addition and subtraction using the column method. When writing down sums, separate the numbers into units, tens, hundreds and thousands. List the numbers in a column and always start adding with the units first.
So when adding together 7948 + 1223, you should write it down like this:
Writing it down
If the numbers are too high or too difficult to subtract in your head, write them down in columns. Always start subtracting with the units first.
The first week back after the holidays, we will be looking at place value. We will be rounding numbers up to 1,000,000 to the nearest 10, 100, 1000, 10000 or 100000.
Giving the complete number for something is sometimes unnecessary. For instance, the attendance at a football match might be 23745. But for most people who want to know the attendance figure, an answer of ‘nearly 24000‘, or ‘roughly 23700‘, is fine.
We can round off large numbers like these to the nearest thousand, nearest hundred, nearest ten, nearest whole number, or any other specified number.
Round 23745 to the nearest thousand.
First, look at the digit in the thousands place. It is 3. This means the number lies between 23000 and 24000. Look at the digit to the right of the 3. It is 7. That means 23745 is closer to 24000 than 23000.