Answer:

Step-by-step explanation:
Divide both sides by 

Simplify:
; 
Answer: 3x-6
Step-by-step explanation:
Let the number be x
3 times the number is 3x
6 less than 3x is 3x-6
(4 hundred + 0 tens + 5 ones) + (1 ten) = 4 hundred + 1 ten + 5 ones
... = 415