50. First and foremost, in the given situation, there are only 2 person, Carl and Tino. Not Three.
=> Carl has 42 inches of ribbon
=> Tino has 2.5 feet of ribbon.
Now, we need to convert this into yard, feet and inches,
let’s have yard first
=> 42 inches = 1.17 yard
=> 2.5 feet = 0.83 yard
=> 1.17 + 0.83
=> 2 yards in total
Now, the feet
=> 42 inches = 3.5 feet
=> 2.5 feet
=> 3.5 feet + 2.5 Feet
=> 6 feet in total
Next is the inches
=> 42 inches
=> 2.5 feet = 30 inches
=> 42 inches + 30 inches = 72 inches in total
