16L=1600 CL (centilitri)
1600 CL ..... 200 km
x CL ......400 km
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x = 1600 * 400 / 200 = 3200 CL = 32 L
1600 CL ..... 200 km
x CL ...... 50 km
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x = 1600 * 50 / 200 = 400 CL = 4 L
1600 CL ..... 200 km
x CL ......350 km
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x = 1600 * 350 / 200 = 2800 CL = 28 L