Hallo Kevin,

additionally to what Ijaz stated:

74LS47 already contains pull-ups of 20...25kOhm. And since the 74LS47 only contains static circuitry these internal pull-up theoretically should be enough to make the chip work.

But:

As pull-ups in combination with stray capacitance always form rather big time constants, rise time at each input is also rather big. This can be troublesome. It's better then to connect an additional pull-up of about 10k to each input (single in line resistor array).
The additional pull-up also helps you to make your application more immune against digital noise.

Have a look at datasheet of your micro, what currents can be accepted at port outputs.

If you want to connect a CMOS gate to Port 0, like CD4XXX or 74HCXX series, then you need an additional pull-up in any case, because there's no one inside.

Kai