Xiaoqiang read a story book. It is known that he read 1 / 3 of the whole book on the first day, 3 / 10 of the rest on the second day, and then read 14 pages every day for five days After reading, how many pages are there in this book? It has to be 90 pages emergency

Xiaoqiang read a story book. It is known that he read 1 / 3 of the whole book on the first day, 3 / 10 of the rest on the second day, and then read 14 pages every day for five days After reading, how many pages are there in this book? It has to be 90 pages emergency


14×(5-2)/[1-1/3-(1-1/3)×3/10]=90
So this book has 90 pages
analysis:
On the first day, I saw 1 / 3 of them,
The next day I saw the remaining 3 / 10, the formula: (1-1 / 3) × 3 / 10
If the total proportion is 1, then the remaining proportion after two days is: 1-1 / 3 - (1-1 / 3) × 3 / 10, which is the proportion of the following three days
Total number of pages viewed in the next three days: 14 × (5-2)
Use the total number of pages read in the next three days / the proportion read in the next three days = the number of pages in the whole book



A story book has 16 pages. Xiaohua said that I read 1 / 80 of the whole book on the first day. He read the remaining 1 / 5 on the second day. How many pages did Xiaohua read on the second day


160 pages, one eighth
The next day I read 160x (1-1 / 8) X1 / 5 = 160x7 / 8X1 / 5 = 140x1 / 5 = 28



Xiaohua read a story book, the first day read 30 pages, the next day read the remaining quarter, there are 60 pages left. How many pages of this book?
It's better not to use equations
fast


1-1/4=3/4
60/(3/4)=80
80+30=110

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