Suppose you have only 2-dollar and 5-dollar bills. Let P(ln) be the statement "We can form n dollars using just 2-dollar and 5-dollar bills." Write the steps in the correct order to prove using strong induction that P(ln) is true for every positive integer n 25.
1. Add another 5-dollar bill, and we have formed k+ 1 dollars, as desired.
2. Because k + 127we know that Pik) is true, that is, we can form k dollars using just 2-dollar and 5- dollar bills.
3. Because k-1 2 5, we know that P(k-1) is true, that is, we can form k-1 dollars using just 2-dollar and 5-dollar bills.
4. Add another 2-dollar bill, and we have formed k + 1 dollars, as desired.
5. The amount $5 can be formed using just one 5- dollar bill, and the amount $6 can be formed by using just three 2-dollar bills. Thus, the statement holds true for k= 5 and k = 6.