Final answer:
The product of 5.4 and 2.4 is 12.96, and the product of 1.67 and 3.5 is 5.845. These calculations were done by first multiplying the numbers as whole numbers and then placing the decimal in the correct position by counting the decimal places from the original numbers.
Step-by-step explanation:
To use vertical calculation to find each product, we must multiply the numbers as if they were integers and then adjust the decimal place in the final answer based on the number of decimal places in the given numbers.
Calculation for (a) 5.4 × 2.4:
Step 1: Ignore the decimal points and multiply the numbers as if they were whole numbers: 54 × 24.
Step 2: Calculate the product of the whole numbers:
54
×24
----
216 (54 × 4)
108 (54 × 20, shift one position to the left)
----
1296
Step 3: Since the original numbers had a total of two decimal places (one in each), place the decimal point in the product so that it has two decimal places as well: 12.96.
The product of 5.4 and 2.4 is 12.96.
Calculation for (b) 1.67 × 3.5:
Step 1: Again, ignore the decimal points: 167 × 35.
Step 2: Calculate the product of the whole numbers:
167
× 35
----
835 (167 × 5)
501 (167 × 30, shift one position to the left)
----
5845
Step 3: There are three decimal places in total in the original numbers (two in the first number and one in the second), so the product must have three decimal places: 5.845.
The product of 1.67 and 3.5 is 5.845.