The total number of nodes for 4d orbital is:

For 4d orbital,  n=4 and $\mathcal{l}$ =2.
Number of radial nodes =n−$\mathcal{l}$−1=4−2−1=1
Number of angular nodes =$\mathcal{l}$=2

Total no. of nodes.= n-1$=4-1=3$