150 = 12
150 +150 = 300 which = 24
150 + 150 + 150 = 450 which =36
the remaining 50 is 12 ÷ 3, so 4. 36 + 4 = 40.
therefore, 40 L of gasoline are needed to go 500km
It would be: 6 1/4 * 1 5/7
= 25/4 * 12/7
= 300/28 = 150/14 = 75/7
In short, Your Answer would be 75/7 or 10 5/7 Pounds
Hope this helps!