Apples account for 4/(3+4+6)=4/ 13.

Pomelo 6/13-4/13 = 2/13

Actually, it's 80 kilograms more.

So a * * * 80 ÷ 2/ 13 = 520kg.

therefore

Grapefruit 520×6/ 13=240 kg.

Apple 520× 4/13 =160kg

Pear 520-240-160 =120kg