We break 1400 down into prime factors: 1400 / \ 100 14 / \ /\ 10 10 2 7 /\ /\ 2 5 2 5 1400 =So the power of 2 on the left must equal the power of 2 on the right, so a=3. The power of 5 on the left must equal the power of 5 on the right, so b=2. And then c=7. Edwin