Mar 8:5 How many loaves have you?
Alternative: What is the value of the loaves you have?
These same Greek words are also used in Mar 6:38 and I already discussed the symbolic aspects of bread in my post about that verse, but another interesting aspect of these words is the multiple meanings of the Greek word used for "how many." Unlike English, in the ancient Greek, the same word is used for questions both of quantity and value.
Christ asks this question prior to physically multiplying the bread, but he is also demonstrating that he can change the purpose and meaning of the bread beyond simply multiply it. Meeting the challenge of the double meaning in the previous verse, Christ offer the bread not only a physical nourishment, which has a temporary value, but as a proof of his teaching, which has a timeless value. He will set people free, but only after they have been given a philosophy that satisfies them. This, of course, also refers to his later changing the value and nature of bread at the Last Supper in communion.
"How many" is from posos (posos), which means "of what quantity," [in distance] "how far." [of number] how far," [of time] "how long," [of value] "how much," "how great," "how many," and "how much."
"Loaves" is from artos (artos), which means specifically a "cake of whole wheat break," and generally "loaf," and "bread."
"Do you have" is from echô (echo), which means "to have," "to hold," "to possess," "to keep," "to have charge of," "to maintain," "to hold fast," "to bear," "to keep close," "to keep safe," and "to have means to do."