2.( 185-5)2 = 90 (ton)

Solution: Suppose it takes X days to produce 2400kg nails.

2400:X= 1600:5

X=2400×5÷ 1600

X=7.5

A: It takes 7.5 days.

4.2/5-3/10 =10 ÷110 =100 (kg)

5.480-80 = 400km 400 ÷ 4 =100km100-53 = 47km/h.

6.1600× 60% = 960kg 960 ÷ 4/3 = 720kg

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