Answer:
length of the longest pencil that can fit must be less than 13cm
Step-by-step explanation:
To get the longest pencil that fit the case, we will use the pythagoras theorem;
diameter = 10cm
radius = 10/2
radius = 5cm
Height = 12cm
Get the length of the longest side
l² = r²+h²
l² = 5²+12²
l² = 25 + 144
l² = 169
l = √169
l = 13cm
Hence the length of the longest pencil that can fit must be less than 13cm
