How to build a low pass filter with limited resources?
Adding capacitors in parallel adds their capacitance together: Cp=C1+C2.
Adding resistors in series adds their resistance together: Rs=R1+R2.
This is by far not the ideal way of doing things, but if you have very limited resources it is one way to do things. Keep in mind the ESR of the capacitance also lowers when adding them in parallel which may have unintended consequences for your application.