Three numbers are in the ratio 3 : 7 : 2, and their LCM is 5376. Their HCF is:
128
Since 3, 7 and 2 are pairwise coprime, the LCM of the ratio terms is \(3\times7\times2=42\).
If the numbers are 3k, 7k and 2k, their LCM is \(42k\).
Setting \(42k=5376\) gives \(k=128\), which is also the HCF since the ratio terms are coprime.
Hence, the HCF of the three numbers is 128.
Six bells begin to toll together and toll, respectively, at intervals of 3, 4, 6, 7, 8 and 12 seconds. After how many seconds, will they toll together again?
A and B are two prime numbers such that A > B and their LCM is 209. The value of A 2 - B is:
Find the least number which when divided by 12, 18, 24 and 30 leaves 4 as remainder in each case, but when divided by 7 leaves no remainder.
Calculate the HCF of \(\frac{12}{5}\) , \(\frac{14}{15}\) and \(\frac{16}{17}\) .
Three numbers are in the proportion of 3 : 8 : 15 and their LCM is 8280. What is their HCF?