A bricklayer lays 649 bricks the first day, 632 the second day, and 478 the third day. Without using a calculator, determine how many bricks the worker laid during the three-day period.
a. 1,759
b. 1,760
c 1,769
d. 1,770
The correct answer and explanation is:
The total number of bricks laid by the bricklayer over the three days is the sum of the bricks laid on each individual day. Let’s add them together:
- On the first day, the bricklayer laid 649 bricks.
- On the second day, the bricklayer laid 632 bricks.
- On the third day, the bricklayer laid 478 bricks.
To find the total number of bricks laid over the three days, we simply add the quantities:
649 + 632 = 1,281
Next, add the result to the number of bricks laid on the third day:
1,281 + 478 = 1,759
Therefore, the correct total number of bricks laid over the three days is 1,759.
The addition process involves simple steps: first adding the first two numbers, and then adding the result to the third number. By working with rounded numbers or estimates, the operation remains straightforward without needing advanced techniques or a calculator. For example, 649 and 632 are close to 650 and 630, so it’s easy to estimate the sum as just over 1,280. Adding 478 to that gives an accurate result of 1,759. The process reinforces basic addition skills and the ability to break down multi-step operations into manageable parts.