If a,b,c,d are in proportion,then
ab=cd
ad=bc
ac=bd
ab=dc
Four numbers a,b,c,d are said to be in proportion if a:b and c:d are equivalent ratios.
So, ab=cd.
Cross-multiplying the values, we get
Hence, option (B) is correct answer.
If x,y,a,b are in proportion , then