Shadow length: 0.50.60.81.1.21.41.5.

Rod length:11.21.622.42.83

1, divided by the length of the shadow, the commercial capital is 0.5. Law: At the same time and place, the quotient of shadow length divided by rod length is equal.

The shadow length of my building is 3.8m, 3.8× 2 = 7.6m, and the height of my building is about 7.6m.. ..

Question 28:

2.4 tons = 2400 kg

Selling by grade: 2400× 1.8 = 4320 (RMB)

If it is sold by grade: because more than half of them reach 1 grade, the rest reach grade 2, according to the meaning of the question.

Assume that 1 300kg reaches grade1,1/00kg reaches grade 2, and the formula is as follows.

1300× 2.4+1100×1.6 = 3120+1760 = 4880 (yuan)

4880 yuan > 4320 yuan, so it is more cost-effective to sell in different grades.

I'm with you 1 Soviet education! Give points if you think it's ok.