Assume that the average gene size in a prokaryotic genome (listed in Table 3-3) is about 1000

Question:

Assume that the average gene size in a prokaryotic genome (listed in Table 3-3) is about 1000 bases pairs in the smaller prokaryotic genomes and 1400 base pairs in the larger bacterial genomes. What is the average number of genes in the smallest and largest prokaryotic genomes shown in the table if all of the DNA in these organisms is part of a gene?