The first one is greater. Adding 3.2 and 0.2 is easy! It's 3.4! Make that 3. Make 6.9, 7. 7×3=21. For the first one, make 1.9, 2. Then Make 3.15, 3. 5×5=25. That is why the first one is greater.
an = 2 an-1 means that each term in the sequence( except the first) is obtained by multiplying the last term by 2, so the first 4 terms are m, 2m, 4m, 8m.
