How many 2 cm square tiles do I need to cover a box that is 26 cm length, 15 cm wide and 8cm high

510

Step-by-step explanation:

(26x15) + (26x15) + (8x15) + (8x15) = 1020

1020 / 2 = 510

(n^3 - n)

= n(n-1)(n+1)

since it is divisible by 3 and 2 ,because it is a multiple 3 consecutive number

if, n-1 is odd then n+1 is also odd, then it is a multiple of 9

but if, n-1 is even then n+1 is also even, then it is a multiple of 4

so, largest multiple = max(9*2, 4*3) = max(18, 12) = 18