Answer:
9 : 3 : 4 = agouti : black : albino
Explanation:
Given,
aa would not allow pigmentation resulting into albino mouse. So,
AaBb = agouti fur
aabb = albino fur
AaBb X aabb :
A_B_ = 9 = agouti
aaB_ = 3 = albino
A_bb = 3 = black
aabb = 1 = albino
Hence, expected phenotypic ratio in the progeny would be =
9 : 3 : 4 = agouti : black : albino