We can't say what the individual costs might be.....but....let's just say that each is at the midpoint of its interval
So....the estimated mean with this assumption is
[ 4(25) + 8(75) + 7(125) + 10(175) + 11(225) ] / [ 4 + 8 + 7 + 10 + 11 ] =
5800 / 40 =
145
Find the estamate mean
