It takes one man one day to dig a 2m x 2m x 2m hole. How long does it take 3 men working at the same rate to dig a 4m x 4m x 4m hole?

x = rate of one man = 23 m3/ 1 day = 8m3/day
3x = rate of three men = 3(8m3/day) = 24m3/day
64m3/(24m3/day) = 2 2/3 days
Is this correct?