Solving by Using Decimal Addition

Question

Race volunteers place flags to mark the trails for a race. Each flag needs to be outlined with reflective tape. How many inches of tape are needed for each flag?
6.8
14.25 in.
Trail Race
13.6 in.
We'll need to find the
of the shape of the flag.
To do that, add the side lengths.
Add zeros in the hundredths places where needed.
11
14.25
13.60
+ 6.80
in.
Estimate to check the answer:
+ 14 + 7 =
This is close to 34.65 inches, so the answer is reasonable.

Answer 1

To find the total inches of tape needed for each flag, we need to add the lengths of the sides of the flags together. The side lengths are:

• 14.25 inches
• 13.6 inches (which we can express as 13.60 inches for easier addition)
• 6.8 inches (which we can express as 6.80 inches for easier addition)

Now we can add these lengths together:

  14.25
+ 13.60
+  6.80
--------

Aligning the numbers with their decimal points:

  14.25
+ 13.60
+  6.80
--------

Now we can add from bottom to top:

1. Hundredths place: 5 + 0 + 0 = 5
2. Tenths place: 2 + 6 + 8 = 16 (write down 6 and carry over 1)
3. Units place: 4 + 3 + 6 + 1 (carried over) = 14 (write down 4 and carry over 1)
4. Tens place: 1 (carried over) + 1 + 1 = 3

Putting it all together, we get:

  14.25
+ 13.60
+  6.80
--------
  34.65

Thus, the total inches of tape needed for each flag is 34.65 inches.

Estimating to check the answer:

• Rounding each number:
  • 14.25 to 14
  • 13.60 to 14
  • 6.80 to 7

Adding these rounded numbers gives us 14 + 14 + 7 = 35, which is indeed close to our computed total of 34.65 inches, making our answer reasonable.

Therefore, the total amount of tape needed for each flag is 34.65 inches.