2 prices for different quantity of same product

[bozley_john_bozley]

dear all... going bald rapidly - help required!!!

i have products of the same price [15.00] but i'm trying to get the price to change to 10.00 once somebody buys a sixth... and then every additional item to stay at 10.00 - it doesn't come across as being too complicated and i've already tried various methods but when an additional item is added to the sixth item when continuing to shop, it adds it as 15.00 rather than continuing at 10.00 - sorry, my explanation maybe lacking

thank you in advance B_J_B