Answer:
1,239
Step-by-step explanation:
This problem can be rewritten as 21 • (6.3 • 10 - 4)
Following the order of operations (PEMDAS) we first have to solve what's in the parentheses.
The next letter is M for multiplication so we have to do 6.3 times 10 which makes 63. That makes 63 - 4 which is 59.
Lastly, since we finished the parentheses, we then do 21 • 59, which solves to be 1,239.