Yes, it’s true, because it’s more than 3, but less than 4
You may recognize that ∆WYZ is a 3-4-5 right triangle. Without any work, then
c = 5
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If you don't remember that a right triangle with legs 3 and 4 has a hypotenuse of 5, you can compute it using the Pythagorean theorem.
c² = 3² + 4²
c² = 9 + 16 = 25
c = √25 = 5
Answer:
The sin A expressed in ratio form is 
Step-by-step explanation:
From the given right angled triangle diagram, sin A is calculated as follows;

Therefore, the sin A expressed in ratio form is 
Let n be the number 18=60% of n
18=0.6n
18/0.6=n
30=n