This one is super difficult, I see your struggle but the answer is A.
Answer:
Step-by-step explanation:
Reduce the ratio to lowest terms, then multiply numerator and denominator by any same value to get another equivalent.

Looking at number 4, you first have to look at the information that you have:
On tuesday he practiced for 1 5/6 hrs
Monday he practiced for 7/10 hrs
He is supposed to practice for 1 1/4 hr.
You could write questions like:
How much more did Marco practice on Tuesday than he is supposed to practice?
This works because it does indeed involve subtraction, you would be subtracting the amount that he should have practiced from the amount of time that he did practice.
If I didn't answer the question, please message me and I will clarify!
Answer:
x = 21, m∠A = 23°, the measure of angle in the right = 67°
Step-by-step explanation:
The angles of a triangle sum up to 180°.
Right angles equals to 90°.
Thus, (2x - 19)° + (3x + 4)° + 90° = 180°
=> 5x + 75 = 180
=> 5x = 105
=> x = 21
m∠A=> 2(21) -19 = 23°
the measure of angle in the right=> 3(21) + 4 = 67°