1.1 Place value and ordering numbers — Practise with help
Work each one first. Reveal a hint only if you are stuck, and the full working only to check.
Warm-up: remember
- Write down the value of the digit in .
- Work out .
- Which is larger, or ?
Answers
- (six tens).
- .
- .
Practise with help
1. Write the value of the digit in each number: (a) ; (b) ; (c) .
Hint
Name the column the sits in: ones, tens, tenths, hundredths?
Full working
(a) hundreds, so . (b) hundredths, so . (c) tenths, so .
2. Work out: (a) ; (b) ; (c) .
Hint
Moving digits: each multiply by 10 shifts one place left; each divide by 10 shifts one place right.
Full working
(a) . (b) . (c) .
3. Insert , or : (a) ; (b) ; (c) .
Hint
Write each pair with the same number of decimal places, or picture them on a number line.
Full working
(a) , so . (b) is further left, so . (c) , so .
4. Write these in order, smallest first: .
Hint
Pad to three decimal places: .
Full working
, so .
5. The temperature at 6 am was and by noon it was . Which temperature is lower? By how many degrees did it rise?
Hint
Sketch a number line from to . The rise is the gap between the two marks.
Full working
is lower. The rise is .
6. A shop lists four prices: , , and . Put them in order and say which is the cheapest.
Hint
Pad to three decimal places and compare.
Full working
, so the cheapest is .