2.57 is the anwser. it comes out to be 2.56666667 which woukd round up to 2.57
The easiest variable you can solve for first is "z". Knowing that opposite angles of a quadrilateral inscribed in a circle are supplementary, subtract 93 from 180 to get z.
Z should equal 87.
The next variable we can solve for is "x". We know that inscribed angles are half the measure of their intercepting arc, so we know 93 is half of (112 + x). The equation would look like this:
93= (112 + x)/2
Multiply both sides by 2
186 = 112 + x
Subtract 112 from both sides
74 = x
Now we can apply the same method we used to find "x" to find y. Set up an equation like this:
80 = (y + x)/2
Substitute the value of x in
80 = (y + 74)/2
Multiply both sides by 2
160 = y + 74
Subtract 74 from both sides
86 = y
Hope this helps!
1500 + 0.45x < 1.70x
1500 < 1.70x - 0.45x
1500 < 1.25x
1500/1.25 < x
1200 < x.....so she would have to sell 1201 cards to make a profit
To express a decimal number (with a finite decimal expression) in a fraction, you work like this: the numerator is the number without decimale separator (you simply pretend it's not there), while the denominator will be 
, where n is the number of digits after the decimal separator.
So, in your case, the number without decimal separator is 53, and you have two digits after the decimal separator, so the fraction will be
which is irreducible.
