A worker processes a batch of machine parts. He completes 15 of the task in the first day, 13 of the rest in the second day, and 56 in the first two days. How many parts are there in this batch?

A worker processes a batch of machine parts. He completes 15 of the task in the first day, 13 of the rest in the second day, and 56 in the first two days. How many parts are there in this batch?

(1-15) × 13 = 45 × 13 = 41556 ^ (15 + 415) = 56 ^ 715 = 120 (pieces) a: there are 120 parts in this batch

A worker has finished 40% of a batch of parts. If he processes 80 more parts, he will finish 1 / 2 of the task. How many parts have been processed?
Order + process

80 ÷ (1 / 2-40%) × 40% = 800 × 40% = 320

The workers processed 15 machine parts and completed seven fifths of the task on the first day and three fifths of the task on the second day. How many parts were completed in two days

10 parts

For the transportation of two vehicles, the ratio of the number of vehicles of a to B is 5:3. If 14 vehicles of a are transferred to B, the ratio of the number of vehicles of a to B is 1:2, how many vehicles are there?

Let X be a cardinal number, then the number of vehicles of a is 5x and the number of vehicles of B is 3x;
After a transfers 14 vehicles to B, the number of vehicles of a becomes 5x-14, while the number of vehicles of B becomes 3x + 14
Since the new ratio is 1:2, 5x-14 / 3x + 14 = 1 / 2
By solving the equation of one variable, we get x = 6, so the number of vehicles of a is 6 * 5 = 30, and the number of vehicles of B is 6 * 3 = 18