To find how many Japanese yen $1 was worth in 2010 and 2013, you will create ratios with the information we know and then solve for the number of yen.
2010:
100 yen x yen (use cross products to solve for x yen)
$0.88 = $1
100 = 0.88x
0.88 0.88
x = 113.6 yen
In 2010, $1 was worth approximately 114 yen.
2013:
100 yen x yen
$0.93 = $1
100 = 0.93x
0.93 0.93
x = 107.5
In 2013, $1 was worth approximately 108 yen.