Correct spelling


Correct spelling, explanation: equipped is a tricky word because at the first glance there is no consonant-vowel-consonant combination, so it doesn’t seem like p should be doubled. However in the case of q standing before u, u behaves like a consonant, so technically we have the combination in the case of equip. Therefore equipped is the correct spelling and equiped is incorrect.

Definition of equipped:
verb, past simple and past participle form of equip, to provide with needed supplies, to furnish
I equipped the kitchen today with a new coffee machine and a toaster.
adjective, to be fully provided with what is needed
Are we fully equipped for tomorrow’s hiking?

Incorrect spelling


Incorrect spelling, explanation: equiped is an incorrect form because u standing after q is treated like a consonant, so there is a consonant-vowel-consonant combination at the end of equip. In such a case, we double the last consonant when we add a suffix (equip plus -ed is equipped), so equipped is the correct form.