Tenths and Hundredths
Class 5 · Mathematics
4 ideas in Class 5 Mathematics, explained in plain words, with games and quizzes to practise.
Millimetres as Tenths of a Centimetre
Part of: Tenths of a centimetre
On a ruler, the gap between two centimetre marks is cut into 10 tiny equal parts. Each tiny part is one millimetre, which is one-tenth of a centimetre, written 0.1 cm. So a leaf that is 4 cm and 7 mm long is 4.7 cm long.
Why it matters. Real objects are rarely an exact number of centimetres. Without tenths, children cannot say how long a seed, a crayon or a bug really is.
Try it in two minutes
- Give your child a ruler and a small object such as a rice grain or an eraser.
- Ask: how many full centimetres? Then count the small marks after that.
- Say the length two ways, for example 3 cm 2 mm and 3.2 cm.
- Ask: which is longer, 25 mm or 2.8 cm? Check on the ruler.
Try at home. Measure five small things at home and write each length in centimetres with a decimal point.
Rupees and Paise as Decimals
Part of: Money and hundredths
One rupee has 100 paise, so one paisa is one-hundredth of a rupee, written ₹ 0.01. Fifty paise is ₹ 0.50 and 5 paise is ₹ 0.05. The digits after the decimal point show the paise.
Why it matters. Children meet prices like ₹ 12.50 in shops and bills. If they misread the digits after the point, they get change and totals wrong.
Try it in two minutes
- Make a pretend shop with price tags such as ₹ 3.50 and ₹ 6.25.
- Ask your child to read each price as rupees and paise.
- Give a ₹ 10 note and ask: how much change will come back?
- Ask: is 5 paise written ₹ 0.5 or ₹ 0.05? Why?
Try at home. Look at a grocery bill together and ask your child to read three prices aloud as rupees and paise.
Tenths and Hundredths of a Whole
Part of: Hundredths of a whole
Cut a square sheet into 10 equal strips and each strip is one-tenth, or 0.1. Cut each strip into 10 boxes and the sheet has 100 boxes, so each box is one-hundredth, or 0.01. Ten boxes make one strip, so 10/100 is the same as 1/10, 0.1 and 0.10.
Why it matters. Decimals are fractions with 10 or 100 equal parts. Seeing them on a grid stops children from thinking that 0.05 is bigger than 0.5.
Try it in two minutes
- Draw a square on paper and split it into 10 strips, then each strip into 10 boxes.
- Colour 3 strips. Ask: what part is coloured? Say it as 3/10 and as 0.3.
- Colour 7 more single boxes in another colour. Ask: how many boxes out of 100? Say it as 0.07.
- Ask: which is bigger, 0.5 or 0.25? Check by colouring.
Try at home. Ask your child to colour 0.45 of a grid in a design and explain how many boxes that is.
Metres, Centimetres and Decimal Sums
Part of: Metres, centimetres and decimals
One metre is 100 centimetres, so one centimetre is one-hundredth of a metre. A height of 3 m and 45 cm is written 3.45 m. Taking away works like money: 2 m minus 1.35 m is 0.65 m, because 65 cm more is needed to reach 2 m.
Why it matters. Heights, jumps, cloth lengths and temperatures are all given as decimals. Children need to read and compare them in daily life.
Try it in two minutes
- Mark 1 m on a wall with tape or use a metre scale.
- Measure your child's height and say it as metres and centimetres, then as a decimal.
- Ask: how much more to reach 2 m? Subtract using centimetres.
- Note two temperatures from a weather report and ask for the difference.
Try at home. Measure the heights of two family members and find how much taller one is, in metres.
What your child will practise
- Metres, Centimetres and Decimal Sums: Jungle Puzzle (Clue Puzzle)
- Millimetres as Tenths of a Centimetre: Ocean Quick Fire (Quick Fire)
- Rupees and Paise as Decimals: Desert Quest (Flip and Match)
- Rupees and Paise as Decimals: Treasure Quest (Collect the Answer)
- Tenths and Hundredths of a Whole: Number Sort (Sort It Out)
- Quiz: Metres, Centimetres and Decimal Sums (8 questions)
- Quiz: Millimetres as Tenths of a Centimetre (8 questions)
- Quiz: Rupees and Paise as Decimals (8 questions)
- Quiz: Tenths and Hundredths of a Whole (8 questions)