Memory Numerical PrefixesVersion en ligne Practice identifying number-based prefixes. par Marc Hughes A dollar has... 10 Tricycle Four identical siblings would be... Some that happens biannually takes place... Octopus 3 Quadruplets every two years. 4 100 quad- deca- octo- A three wheeled bike 8 tri- Eight legged sea creature One hundred pennies Ten years is a... centi- decade