To find out how many days it will take Onny to save enough money for the guitar, you can divide the total cost of the guitar by the amount he saves each day.
Total cost of the guitar: 600
Amount saved per day: 2
Now, divide the total cost by the daily savings:
\[ \text{Number of days} = \frac{600}{2} = 300 \]
So, it will take Onny 300 days to save enough money to buy the guitar.