A batch of goods will be transported by car a in 4 hours, car B in 8 hours, and car C in 10 hours

A batch of goods will be transported by car a in 4 hours, car B in 8 hours, and car C in 10 hours

1 ÷ (1 / 4 + 1 / 8 + 1 / 10) = 40 / 19 hours
It takes 40 / 19 hours for three vehicles to be transported together

Party A and Party B transport a batch of goods to a 315 km construction site. Party A starts 0.5 hours later than Party B, but arrives 1.3 hours earlier. It is known that the speed ratio of the two vehicles is 7:5
To solve by proportion

A school organized 340 teachers and students to carry out long-distance inspection activities, with 170 Pieces of luggage. It plans to rent 10 cars of two models a and B. It is understood that each car of a can carry up to 40 people and 16 pieces of luggage, and each car of B can carry up to 30 people and 20 pieces of luggage. (1) please help the school to design all feasible car rental schemes; (2) if the rent of car a is 2000 yuan per car, the rent of car B will be reduced It's 1800 yuan per car. What's the best way to save car rental?

(1) According to the meaning of the title, we can get 40x + 30 (10 − x) ≥ 34016x + 20 (10 − x) ≥ 170, and the solution is 4 ≤ x ≤ 7.5. Also, X is an integer, ∧ x = 4 or 5 or 6 or 7. There are four schemes: ① a 4, B 6; ② a 5, b 5; ③ a 6, B 4; ④ a 7

A school organized 340 teachers and students to carry out long-distance inspection activities, with 170 Pieces of luggage. It plans to rent 10 cars of two models a and B. It is understood that each car of a can carry up to 40 people and 16 pieces of luggage, and each car of B can carry up to 30 people and 20 pieces of luggage. (1) please help the school to design all feasible car rental schemes; (2) if the rent of car a is 2000 yuan per car, the rent of car B will be reduced It's 1800 yuan per car. What's the best way to save car rental?

(1) According to the title, 40x + 30 (10 − x) ≥ 34016x + 20 (10 − x) ≥ 170, the solution is 4 ≤ x ≤ 7.5. Also, X is an integer, ∩ x = 4 or 5 or 6 or 7. There are four schemes: ① a 4, B 6; ② a 5, b 5; ③ a 6, B 4; ④ a 7, B 3. (2) ① a 4, B 6; the total cost is 4 × 2000 + 6 × 1800= The total cost is 5 × 2000 + 5 × 1800 = 19000 yuan; the total cost is 6 × 2000 + 4 × 1800 = 19200 yuan; the total cost is 7 × 2000 + 3 × 1800 = 19400 yuan; because the rent of car B is less, the more car B, the less the total cost