(b) A, B and C are sureties to D for the sum of 1, 000 rupees lent to E, and there is a contract between A, B and C that A is to be responsible to the extent of one- quarter, B to the extent of one- quarter, and C to the extent of one- half. E makes default in payment. As between the sureties, A is liable to pay 250 rupees, B 250 rupees, and C 500 rupees.