Answer:
The correct option is (d)-He wrote commutative instead of associative in Step 2.
Step-by-step explanation:
Commutative property: 
Associative property:
Now consider the provided expression.
(6.2 − 1.6) − 4.4 + 7.8
Step 1
(6.2 − 1.6) − 4.4 + 7.8
Step 2 Use Associative property
6.2 + (−1.6 − 4.4) + 7.8
Step 3: Simplify
6.2 − 6 + 7.8
Step 4: Use commutative property
14 − 6
Step 5: Simplify
14 − 6 = 8
Hence, the wrong step is step 2. He wrote commutative instead of associative in Step 2.
Therefore, the correct option is (d)-He wrote commutative instead of associative in Step 2.
B. 6.72the answer is B 6.72
Answer:
13
Step-by-step explanation:
To obtain a term in a Fibonacci sequence, add the previous 2 terms, thus
7 th term = 8 + 5 = 13
Here's what I'd do. If the account loses $4 per month, and it currently has $412, then do 412/4, which is 103 months. So in 103 months, or about 8 1/2 years, the bank account will be out of money.
The answer is the square root of 44