In parallel connection, the formula to calculate n resistance is
1/R= 1/R1 +1/R2 +......+1/Rn
When 2 resistance are connected in parallel the net equivalent resistance will be smaller. Let us take an example:
R1 =10( larger resistance ) R2=5( smaller resistance)
Equivalent resistance R=(R1*R2)/R1+R2)
=50/15 = 3.33 ohm (which is less than R2)