Answer:
$251
Step-by-step explanation:
Let x be the number of ounces for the additional cost, we can write an expression to determine the cost of 10-ounce envelope. The first ounce is $54 therefore the remaining 9 ounces wiht cost $22.
[tex]53+22\cdot{x}=53+22\cdot{9}=53+198=251[/tex]
The cost of mailing 10 ounces envelope is $251