Four fair dice D1,D2,D3 and D4 each having six faces numbered 1, 2, 3, 4, 5 and 6 are rolled simultaneously. The probability that D4 shows a number appearing on one of D1,D2 and D3, is ?
D1, D2, D3 and D4 are rectangles with areas 8 m2,6 m2,9 m2 and 4 m2 respectively. Which is the 'biggest' rectangle?