Answer :
Final answer:
The two Christmas tree bulbs flashing every 10 and 15 seconds will next flash simultaneously in 30 seconds, as 30 is the least common multiple of 10 and 15.
Explanation:
A flash bulb on a Christmas tree flashes once every 10 seconds and another bulb flashes once every 15 seconds. If they are flashing together now, we need to find the least common multiple (LCM) of 10 and 15 to determine when they will flash together next.
To find the least common multiple of 10 and 15, we can use the prime factorization method. The prime factorization of 10 is 2 * 5 and the prime factorization of 15 is 3 * 5. We take all the unique factors and multiply them together, so our answer is 2 * 3 * 5 = 30 seconds.
Therefore, the two bulbs will flash simultaneously next at 30 seconds from now.
Learn more about Least Common Multiple here:
brainly.com/question/34291727
#SPJ11