I need an actual explanation and answer.
Hayley has a new sticker album with 250 gaps, each of which requires a particular sticker to fill it. The stickers to fill these gaps are sold individually in opaque sealed packets, so the contents of a packet are not known until the packet is purchased and opened.
Each packet costs 20 cents. But instead of buying every sticker individually, Hayley can write to the publisher of the album and request 25 specified stickers for $12.50, 50 for $25, 75 for $37.50 and so on.
Assuming there is an equal chance of a packet containing any of the 250 stickers how many different individual stickers shold Hayley collect before ordering one or more packs of 25 if she wants to minimize the expected cost of collecting a full set of stickers?
Hint: The number is divisible by three.
Anyone have the answer?
Hayley has a new sticker album with 250 gaps, each of which requires a particular sticker to fill it. The stickers to fill these gaps are sold individually in opaque sealed packets, so the contents of a packet are not known until the packet is purchased and opened.
Each packet costs 20 cents. But instead of buying every sticker individually, Hayley can write to the publisher of the album and request 25 specified stickers for $12.50, 50 for $25, 75 for $37.50 and so on.
Assuming there is an equal chance of a packet containing any of the 250 stickers how many different individual stickers shold Hayley collect before ordering one or more packs of 25 if she wants to minimize the expected cost of collecting a full set of stickers?
Hint: The number is divisible by three.
Anyone have the answer?