50 और 80 के बीच कितनी अभाज्य संख्याएँ (prime numbers) मौजूद हैं?

Four consecutive prime numbers are arranged in ascending order. The product of the first three is 105 and that of the last three is 385. The largest given prime number is:

What is the sum of all prime numbers greater than 40 and less than 60?

What is the sum of all the prime numbers between 12 and 49?