SQUARES IN STREETS
150. The square of the number of my house is equal to the difference of the squares of the numbers of my next door neighbour’s houses on either side.
My brother, who lives in the next street, can say the same of the number of his house, though his number is not the same as mine. How are our houses numbered?
151.
Two men of unequal strength are set to move a block of marble which weighs 270 lbs., using for the purpose a light plank 6 feet long. The stronger man can carry 180 lbs. How must the block be placed so as to allow him just that share of the weight?
152.
A man has twenty coins, of which some are shillings and the rest half-crowns. If he were to change the half-crowns for sixpences and the shillings for pence he would have 156 coins. How many shillings has he?