Question

Joshua spent 3/7 of his money on souvenirs on his vacation. He has $16 left. How many did he spent on souvenir

Answer 1

Let us assume the total amount of money Joshua had = x
Amount of money Joshua had left after spending on souvenir = $16
Then
(3x/7) + 16 = x
3x + 112 = 7x
112 = 7x - 3x
112 = 4x
x = 112/4
   = 28
Now
The amount of money spent on souvenir = (3/7) * 28
                                                                 = 3 * 4 dollars
                                                                 = 12 dollars
So the total amount of money spent on souvenirs by Joshua is $12

Answer 2

He spent $12 on souvenirs