We know that the cost of the meal is $40 and the tip is the 10%.
And we must find the total cost.
The total cost will be we cost of the meal plus the tip.
Now, we must find the cost of the tip.
Since the tip is the 10% we must multiply the cost of the meal by 10%. (We can represent 10% as 0.1)
Then, the total cost is
Finally, the total cost of the meal is $44.