A log is 18 m long, correct to the nearest metre - OCR - GCSE Maths - Question 12 - 2017 - Paper 1

To facilitate calculations, we convert the length from meters to centimeters.

1 meter = 100 centimeters,

Thus, the range of the log in centimeters is:

[ 17.5 \text{ m} = 1750 \text{ cm} ] [ 18.5 \text{ m} = 1850 \text{ cm} ]

Each fence post is 80 cm long. We need to determine how many such posts can fit into the length of the log.

To find the maximum number of fence posts, we divide the total centimeters of the log by the length of each post:

[ \text{Number of posts} = \frac{\text{Length of log}}{\text{Length of one post}} ]

Calculating using the minimum length of the log:

[ \frac{1750 \text{ cm}}{80 \text{ cm}} = 21.875 \text{ posts} ] (which we round down to 21 posts)

Now, using the maximum length of the log:

[ \frac{1850 \text{ cm}}{80 \text{ cm}} = 23.125 \text{ posts} ] (which we round down to 23 posts)

Thus, the largest number of fence posts that can possibly be cut from this log is 23.