Problem Set 42 – Subtracting Decimal FractionsClass 5 Maths · Chapter 9 Decimal Fractions · Problem Set 42 – Maharashtra Board

Summary: Problem Set 42 – Subtracting Decimal Fractions

Subtract decimals the same way as whole numbers: decimal points one below the other, start from the right.

If a top digit is smaller, borrow from the place on its left: 1 tenth = 10 hundredths, 1 unit = 10 tenths.

If the numbers have different numbers of decimal places, add zeros: 50.3 − 26.75 → 50.30 − 26.75.

Word problems in metres can be answered in centimetres: 0.06 m = 6 cm.

Metre, gram and litre are basic units. Kilo = 1000, hecto = 100, deca = 10 times bigger; deci = 1/10, centi = 1/100, milli = 1/1000.

Key points to remember

• Decimal points one below the other
• Subtract hundredths first, then tenths
• Borrow 1 tenth = 10 hundredths
• Borrow 1 unit = 10 tenths
• Fill in zeros: 50.3 = 50.30
• Check: answer + smaller number = bigger number
• 0.01 m = 1 cm
• kilo 1000, hecto 100, deca 10, deci 1/10, centi 1/100, milli 1/1000

Problem Set 42 – Subtracting Decimal Fractions – Notes

1. Setting up

• Write the bigger number on top and line up the decimal points.
• Make both numbers have the same number of decimal digits by adding zeros.
• Put the decimal point in the answer line first.

2. Borrowing

• If the top digit is smaller, take 1 from the place on its left.
• 1 tenth taken becomes 10 hundredths; 1 unit taken becomes 10 tenths.
• Then subtract that column and move one place to the left.

3. When the top has fewer decimal places

• 50.3 − 26.75 → write 50.30 − 26.75.
• Hundredths: 0 − 5 → borrow a tenth (3 → 2): 10 − 5 = 5. Tenths: 2 − 7 → borrow a unit; units is 0, so first borrow a ten (5 → 4, units 10), then units 10 → 9 and tenths 12 − 7 = 5.
• Units: 9 − 6 = 3. Tens: 4 − 2 = 2. Answer: 23.55.

4. Word problem in metres and centimetres

• Rohan's plant was 1.36 m tall. A month later it was 1.42 m. How much did it grow?
• 1.42 − 1.36: hundredths 2 − 6 → borrow: 12 − 6 = 6; tenths 3 − 3 = 0; units 1 − 1 = 0 → 0.06 m.
• 0.06 m = 6 hundredths of a metre = 6 cm.

5. Something more: decimal units of measure

• Basic units: metre (length), gram (mass), litre (volume).
• Bigger units go up 10 times each step: deca = 10, hecto = 100, kilo = 1000. 1 kilometre = 1000 m.
• Smaller units become one-tenth each step: deci = 1/10, centi = 1/100, milli = 1/1000. 1 millilitre = 1/1000 litre.
• These prefix names came from Greek and Latin words.

Formulas at a glance

Key terms

Problem Set 42 – Subtracting Decimal Fractions – Flashcards

Read the question, answer it in your head, then tap the card to check. 10 cards.

Problem Set 42 – Subtracting Decimal Fractions – MCQ Quiz

10 questions. Tap an option — you will see at once if it is right and why.

How to study Problem Set 42 – Subtracting Decimal Fractions

⏱ About 25 minutes

1. Learn (5 min)
   Learn to line up points and borrow 1 tenth = 10 hundredths.
2. Subtract (15 min)
   Work sums right to left; add zeros where places are empty. Check by adding back.
3. Practise (5 min)
   Do the 4 'Try it yourself' sums, take the quiz and play 🎮 Play.