The numerator and denominator of a fraction are in the ratio of 1 to 4. if the numerator and denominator are both increased by 2, the fraction is now equal to 2/3. if n = the numerator and d = the denominator, which of the following systems of equations could be used to solve the problem?
a.4n = d and 2n + 4 = 3d + 6
b.4n = d and 3n + 6 = 2d + 4
c. n = 4d and 3n + 6 = 2d + 4
d. n = 4d and 2n + 4 = 3d + 6