Matt is 24 and John is 18. 24 - 18 is 6. And 24 + 18 would equal 42.
The function representing the price of the ring x years after 2000 is f(x) = (100 + 35)/100 *x + 590 = 135/100 *x + 590 = 1.35x + 590
i.e. f(x) = 1.35x + 590
The law of cosines :
A^2 = B^2 + C^2 - 2BC cos A
2^2 = 3^2 + 4^2 - 2 . 3. 4 cos theta
= 21
hope this helps
Solution :
Let A = Economics, B = Mathematics
n(A) = 311, n(B) = 243, 
a). So, 
= 311 + 243 - 135
= 419
b). n(A only) = 311 - 135
= 176
n(B only) = 243 - 135
= 108
Exactly one of these two courses

= 0.568
c). Neither economics nor mathematics


= 0.162