Problem Set 41 – Adding Decimal FractionsClass 5 Maths · Chapter 9 Decimal Fractions · Problem Set 41 – Maharashtra Board

Summary: Problem Set 41 – Adding Decimal Fractions

We add decimals the same way as whole numbers, because decimals use the same place-value system.

Write the numbers so that the decimal points — and so all the places — are one below the other.

Start with the smallest place (hundredths, then tenths), then units, tens…

10 hundredths = 1 tenth and 10 tenths = 1 unit, so carry 1 to the left when a column makes 10 or more.

If one number has fewer decimal digits, fill in zeros: 128.5 = 128.50. Put the decimal point in the answer right under the others.

Key points to remember

• Decimal points one below the other
• Add hundredths first, then tenths
• 10 hundredths = 1 tenth (carry 1)
• 10 tenths = 1 unit (carry 1)
• Fill empty places with 0: 6.5 = 6.50
• Point in the answer goes under the points above
• Half + half = 1: 0.5 + 0.5 = 1.0
• Add units of the same kind (₹ with ₹, m with m)

Problem Set 41 – Adding Decimal Fractions – Notes

1. Why it works like whole numbers

• Each place is still 10 times the place on its right, even after the point.
• So 10 in any column becomes 1 in the next column to the left — that is carrying.
• Two and a half rupees + four and a half rupees: 2.50 + 4.50 = 7.00, because the two halves make 1 rupee.

2. Setting up the sum

• Write one number under the other with the points in a straight line.
• If digits are missing after the point, write zeros: 128.5 + 63.48 → 128.50 + 63.48.
• Put the point in the answer line before you start adding.

3. Adding with carries

• Hundredths: 6 + 9 = 15 → write 5, carry 1 tenth.
• Tenths: 4 + 7 + 1 = 12 → 12 tenths = 1 unit + 2 tenths → write 2, carry 1.
• Units and tens are added as usual.

4. Turn words into decimals first

• Three and a half metres + one and three quarter metres → 3.50 m + 1.75 m.
• Hundredths: 0 + 5 = 5. Tenths: 5 + 7 = 12 → write 2, carry 1. Units: 3 + 1 + 1 = 5.
• Answer: 5.25 m (five and a quarter metres).

5. Money and length sums

• ₹ 245.60 + ₹ 54.40: 0 + 0 = 0; 6 + 4 = 10 → 0 carry 1; 5 + 4 + 1 = 10 → 0 carry 1; 4 + 5 + 1 = 10 → 0 carry 1; 2 + 1 = 3 → ₹ 300.00.
• 46.7 cm + 28.6 cm: 7 + 6 = 13 → 3 carry 1; 6 + 8 + 1 = 15 → 5 carry 1; 4 + 2 + 1 = 7 → 75.3 cm.
• Write the unit with the answer.

Formulas at a glance

Key terms

Problem Set 41 – Adding Decimal Fractions – Flashcards

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

Problem Set 41 – Adding 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 41 – Adding Decimal Fractions

⏱ About 25 minutes

1. Learn (5 min)
   Learn to line up decimal points and fill empty places with 0.
2. Add (15 min)
   Add from the right, carrying 1 whenever a column makes 10 or more.
3. Practise (5 min)
   Do the 4 'Try it yourself' sums, take the quiz and play 🎮 Play.