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The school library has purchased three kinds of books, among which the number of story books accounts for 1 / 3 of the total number, 150 comic books, and the ratio of the number of science and technology books to the total number of the other two books is 1:5. How many of the three kinds of books have been purchased?
Let the total number be X,
Then x / 3 + 150 = 5x / 6,
The solution is x = 300,
A: 300 copies in total
One sixth of the total saplings were planted on the first day, and 36 saplings were planted on the second day. At this time, the ratio of the number of saplings already planted to that of the remaining saplings was 7:11. How many saplings were planted on the first day?
7/(11+7)=7/18
Total number of saplings = 36 / (7 / 18-1 / 6) = 162
Seedlings planted on the first day = 162 * 1 / 6 = 27
The sixth grade mathematics application question
In the experiment class, Xiaoli prepared a cup of salt water, using 20 grams of salt and 80 grams of water; Xiaoning prepared another cup of salt water, using 15 grams of salt and 45 grams of water?
A and B drive from a to B at the same time. A travels 60 kilometers per hour, B 40 kilometers per hour, and a stops for 2 hours. As a result, a and B arrive at B at the same time. How many kilometers is the distance between a and B?
The engineering team built a road, 360 meters in the first week, and the remaining 40% in the second week. At this time, the ratio of the number of meters repaired to the number of meters not repaired is 5:3?
In the experiment class, Xiaoli made a cup of salt water and used 20 grams of salt and 80 grams of water; Xiaoning made another cup of salt water and used 15 grams of salt and 45 grams of water. Xiaoning wanted to make the concentration of salt water and Xiaoli the same (the mass ratio of salt to salt water), how many grams of water should be added? Xiaoli's concentration is 20 △ 20 + 80 = 20% Xiaoning, 15 grams of salt can
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