Question

The length of the longest pencil which can fit in a box measuring 6 cm, 3 cm and 2 cm.

Options

• 7 cm

• 6.5 cm

• 9 cm

• 7.5 cm

Answer 1

7 cm

Explanation:

Step 1: Use the space diagonal formula

The longest pencil is along the space diagonal of the box:

`d = sqrt(l^2 + b^2 + h^2)`

where l = 6 cm, b = 3 cm, h = 2 cm

Step 2: Substitute the values

`d = sqrt(6^2 + 3^2 + 2^2)`

= `sqrt(36 + 9 + 4)`

= `sqrt(49)`

d = 7 cm