5: Un músico golpea un tambor una vez cada 24 segundos exactamente, mientras que otro lo hace cada 14 segundos. Suponiendo que acaban de golpear ambos a la vez, ¿cuándo volverán a coincidir?

168 seconds

Step-by-step explanation:

To find out when they coincide again, the least common multiple between both numbers must be calculated:

24 14 | 2

12   7 | 2

6    7 | 2

3    7 | 3

1     7 | 7

1     1

Therefore the least common multiple is:

2 * 2 * 2 * 3 * 7 = 168

This means that they will coincide again at 168 seconds, when the first musician has struck 7 times (168/24) and the other 12 times (168/14)

because linear equations are a lot simpler than quadratics equations, and linear equations formula is a lot easier to memorize. that's why i think they're harder.