This section deals with the revision of place value.
Remember that we write decimal numbers in the form:
Thousands Hundreds Tens Units . Tenths Hundredths Thousandths
Example 1
Here are some number cards:
1 7 3 5
You can use each card once to make the number 1735, like this:
1 7 3 5
(a) What is the biggest number you can make with the four cards?
(b) Explain why you cannot make an even number with the four cards.
Note: It is often helpful to refer to a number line when comparing values;
a number line can also show negative values:
Remember that the symbol < means 'less than' and > means 'greater than'.
Example 2
Put the correct sign, < or = or >, into each sentence.
(a) -- 7 -- 2
(b) 3 -- 2 -- 5
(c) 3 -- 5 4 -- 6
Example 3
The arrow on this thermometer shows a temperature of 10 °C.
(a) Draw an arrow on the thermometer to show
a temperature of 24 °C.
Label the arrow 24 °C.
(b) Draw an arrow on the thermometer to show
a temperature of -- 4 °C.
Label the arrow -- 4 °C.
(c) The temperature was -- 10 °C.
It went up 15 °C.
What is the temperature now?
(d) Write these temperatures in order, coldest first.
3 °C, -- 10 °C, 0 °C, 20 °C, -- 1 °C
From left to right, pick the smallest possible digit every time. This will give you the smallest possible number.
2359
1349
The smallest is 1111 if repeats are allowed. If not, it is 1235.
To find the smallest number using the digits 1, 2, 3, 4, 5, and 6, we need to arrange them in ascending order. The smallest possible number is 123456. This arrangement ensures that the number is as small as possible because the digits are in their smallest possible positions from left to right.
19
The smallest even 4-digit number using the digits 5, 7, 4, and 9 is 4579. To create the smallest number, we start by placing the smallest digit, which is 4, in the thousands place to ensure it is a 4-digit number. Since we need to make it an even number, the units place must be an even number, so we use 4. Placing 5 in the hundreds place and 7 in the tens place gives us the smallest even 4-digit number, 4579.
It is 4579.
The smallest positive integer is 1357.
Well, isn't that a happy little question! To find the smallest even number using the digits 5, 2, 4, and 7, we should start by arranging them in ascending order. That would give us 2457, which is the smallest even number we can create. Just remember, there are no mistakes in making numbers, only happy little accidents!
If you can use decimals, then the smallest number would be 0.8765321. But if you can't use decimals, then it would be 10235678.
1023456789
123,456 would be the smallest number using all 6 digits. You arrange the numbers from lowest to highest.
From left to right, pick the smallest possible digit every time. This will give you the smallest possible number.
24,578
2359
1349