Take into account that 294 is the 70% of x number of songs.
then, you can write:
(70/100)x = 294
then, to determine the total number of songs Jorge has, solve the previous equation for x:
(70/100)x = 294
0.7x = 294
x = 294/0.7
x = 420
Hence, 420 songs are stored on Jorge's phone