Answer
no he gave him a dollar extra. if his total is 38.70 and gave 50 if you subtract it would be 11.30 not 12.30
Step-by-step explanation:
Answer:
d. 20
Step-by-step explanation:
The given question implies 5 permutation 2, i.e 
.
But,

= 
So that for 
, n = 5 and r = 2.

= 
= 
= 
Cancel out 3 and 2 with respect to the numerator and denominator.

= 5 * 4
= 20
Therefore,

= 20
So that the correct option is D.
Answer: $222.73
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Work Shown:
x = pre-GST price
10% of x = 0.10x = tax amount
x + 0.10x = 1.10x = post-GST price = 245
1.10x = 245
x = 245/1.10
x = 222.7272 approximately
x = 222.73 is the price before tax.
------------
Check:
10% of 222.73 = 0.10*222.73 = 22.273 = 22.27
The tax amount ($22.27) is added to the pre-GST price to get
22.27+222.73 = 245
which matches the post-GST price mentioned.
The answer is confirmed.
Or another way to confirm the answer is to calculate this
1.10*222.73 = 245.003 = 245
I think it measures an angle of 180 degrees