‘X’ grams contain nine gram atoms of calcium. ‘X’ grams contain ‘Y’ gram atoms of magnesium. The value of 'Y' is
‘1’ gram atom of ‘Ca’ = 40 g ;
‘9’ gram atoms of ‘Ca’ = 360 g ;
‘X’ = 360 g ;
‘1’ gram atom of ‘Mg’ = 24 g ;
‘Y’ gram atoms of ‘Mg’ = 360 g (X);
Y = 15 ;