Can 3 × (2 out of 15 + 1 out of 12) - 5 out of 2 be simply calculated as 5 out of 7 + 3 out of 4 × 5 out of 6-3 out of 8? There are 250 pages in a story book. Xiaoming read two fifths of the book on the first day, and one fourth of the book on the second day. How many pages did he read on the second day? How to draw a picture The students of Lenin primary school plan to donate 1680 yuan to the "love project", and they have donated 7 / 21 of the plan. How much have they donated? fast Quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick

Can 3 × (2 out of 15 + 1 out of 12) - 5 out of 2 be simply calculated as 5 out of 7 + 3 out of 4 × 5 out of 6-3 out of 8? There are 250 pages in a story book. Xiaoming read two fifths of the book on the first day, and one fourth of the book on the second day. How many pages did he read on the second day? How to draw a picture The students of Lenin primary school plan to donate 1680 yuan to the "love project", and they have donated 7 / 21 of the plan. How much have they donated? fast Quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick quick

Question 1: 250 * (2 / 5) * (1 / 4) = 25
Question 2: 1680 * (7 / 21) = 560

7 / 12 ﹣ 2.5 ﹣ 4 (simple calculation)

7/120