12. The greatest number which on dividing 1659 and 2036 leaves remainders 8 and 4, respectively is. 13. Find the greatest number of 6 digits exactly divisible by 24, 15 and 36. 14. 144 L of liquid P and 216 L of liquid Q are to be packed in containers of the same size. The minimum numbers of containers required. 15. Three numbers are in the ratio 3:4:5 and their LCM is 1200. Then, their HCF is. 16. Find the number nearest to 110000) but greater than 100000 which is exactly divisible by each of 8, 15 and 21. 17. Two tankers contain 850 L and 680 L of petrol, respectively. Find the maximum capacity of a container which can measure the petrol of either tanker, in exact number of times. 18. Find the HCF of 180, 252 and 324 by using Euclid's division lemma. 19. There are 156, 208 and 260 students in groups A, B and C, respectively. Buses are to be hired to take them for a field trip. Find the minimum numbers of buses to be hired, if the same number and same group of students should be accommodated in each bus. 20. Find the LCM and HCF of 1296 and 2520 by applying the fundamental theorem of arithmetic method i.e using the prime factorization method. 21. Find the largest number that divides 1251, 9377 and 15628 leaving remainders 1, 2 and 3, respectively. 22. On a morning walk, three persons step off together and their steps measure 40 cm, 42 cm and 45 cm, respectively. What is the minimum distance each should walk so that each can cover the same distance in complete steps? 23. There is a circular path around a sports field. Bittu takes 18 minutes to drive one round of the field, while Pappu takes 12 minutes for the same. Suppose they both start at the same point and go in the same direction. After how many minutes will they meet again at the starting point?