• question_answer 38) Four prime numbers are in ascending order of their magnitudes. The product of the first three is 2, 431 and that of the last three is 4, 199. The largest given prime number is A)  11B)  13C)  17D)  19

Let the number be a, b, c and d Given that $a\times b\times c=2,431$       .............(i) and      $b\times c\times d=4,199$      .............(ii) Now, divide equation (ii) by equation (i) $\frac{b\times c\times d}{a\times b\times c}=\frac{4,199}{2431}$$\Rightarrow \frac{d}{a}=\frac{4,199}{2431}=\frac{13\times 17\times 19}{11\times 13\times 17}=\frac{d}{a}=\frac{19}{11}$ Hence, the largest number is 19.