Will a different frequency RAM work?

Question

laptops

In general, there is a laptop RAM ddr3, 1333mhz, but there is a laptop with ddr3 RAM, 1600mhz, will 1333 fit in place of 1600?

Answer 1

Yes, of course, it will work slower (you are unlikely to notice how much slower).
If there are 2 bars - one fast and the other slow, then the speed of both bars will be aligned with the slow one. A fast plank will not be able to work quickly paired with a slow one.