Among three numbers, the first is twice the second and thrice the third. If the average of three numbers is 429, then what is the difference between the first and the third number?
A can do 75% of a job in 9 days and B can do half of the job in 8 days. If they work on it together, then in how many days can they do half of the job?
PQRS is a square, M is the mid-point of PQ and N is a point on QR such that NR is two-third of QR. If the area of ΔMQN is 48 cm2 , then what is the length (in cm) of PR ?