<t>How about this: 1+3 = 44+8 = 129+15 = 2416+24 = 4025+35 = 6036+48 = 84The total is 224, then add 7+7.5, i.e. sqrt(49) + approximating sqrt(50)Total is 238.5. This is effectively a linear estimate of square roots, e.g. for sqrt(4) through sqrt(8) the estimates are: 2, 2.5, 2.5, 2.5, 2.5 and the su...