uno is the answer i believe
Let the number of blue marbles be x
number of yellow marbles = x/3
number of green = x- 90
ATQ
x + x/3 + x - 90 = 694
2x + x/3 = 784
(6x + x)/3 = 784
7x/3 = 784
x = 784 x 3/7
x = 112 x 3
x = 336
number of blue marbles = 336
A product is negative when the number of negative numbers in the multiples is odd.
Therefore, options A and C gives negative products.