Answer:
The number of times coin thrown was 500.
Step-by-step explanation:
Relative\ frequency=\frac{Number\ of\ lands\ on\ heads}{Number\ of\ times\ coin\ thrown}
0.4=\frac{200}{x}
By cross multiplying we get:
0.4x=200
Dividing both sides by 0.4 we get:
x=500.