Category: 05. Add and Subtract Decimal Numbers

Problem 1: Danny and his classmates weighed colored blocks on a scale during a science lab. The blue block weighed 109 grams and the yellow block weighed 87.19 grams. How much more did the blue block weigh than the yellow block? Solution Step 1: The weight of blue block = 109 grams The weight of…

Problem 1: A mixture is obtained by mixing four items of following weights; 132.45 grams, 220.11 grams, 128.62 grams and 140 grams. What is the total weight of the mixture? Solution Step 1: The first item’s weight = 132.45 grams The second item’s weight = 220.11 grams The third item’s weight = 128.62 grams The…

Introduction Subtraction of money in dollars and cents is same as the subtraction of decimal numbers.Rules for subtraction with money Problem 1: Subtract 187.18−187.18−93.49 Solution Step 1: The money amounts to be subtracted are lined up vertically with the decimal points and dollar signs aligned one above the other. Step 2: We begin at the right…

Introduction Addition of money in dollars and cents is same as the addition of decimal numbers.Rules for addition with money Problem 1: Add 134.10+134.10+73.09 Solution Step 1: The money amounts to be added are lined up vertically with the decimal points and dollar signs aligned one above the other’ Step 2: We begin at the right…

Problem 1: Estimate the sum after rounding each number to the nearest tenth 98.09 + 23.41 − 11.30 – 27.85 Solution Step 1 Rounding each term to nearest tenth, the expression becomes = 98.09 + 23.41 − 11.30 – 27.85 = 98.1 +23.4 – 11.3 – 27.9 = 121.5 −39.2 = 82.3 Step 2 So…

Introduction Advanced subtraction of decimals is similar to subtraction of whole numbers with borrowing.Rules for decimal subtraction Problem 1: Subtract 47.324 − 28.75 Solution Step 1: The decimals are aligned as shown. A zero is added to the right of 28.75 as the maximum number of decimal places is 3. Step 2: We start with the…

Introduction Basic subtraction of decimals is similar to subtraction of whole numbers without borrowing.Rules for Decimal Subtraction Problem 1: Subtract 38.48 − 16.3 Solution Step 1 The decimals are aligned as shown. A zero is added to the right of 16.3 as the maximum number of decimal places is 2. Step 2 We start with the…

Introduction Decimals have to be aligned so that digits with same place values are placed one above the other. Such decimals are aligned decimals. The decimals have to be aligned before subtraction is done. Subtraction of aligned decimals is similar to subtraction of whole numbers.Rules for Subtraction of Aligned Decimals Problem 1: Subtract 18.48 − 6.3…

Introduction Addition of three decimals is similar to addition of two decimals.Rules for decimal addition with 3 numbers Problem 1: Add 67.07 + 13.41 + 7.30 Solution Step 1: The decimals are aligned vertically above one another as shown. Step 2: We begin at the rightmost column 7 + 1 + 0 = 8; moving left 0 +…

Definition The decimals are aligned so that the digits of same place values are above and below each other. Such decimals are aligned decimals. It is necessary that the decimals are aligned before addition. Addition of aligned decimals is similar to addition of whole numbers.Rules of decimal addition: So, at first the decimals are aligned…