A student appears for 4 papers-english,math,physics,chemistry.Max Marks for which are in the ratio 1:1:2:2. His marks are in the ratio of4:8:13:15. If he got 80% of the total max marks, in how many papers did he got more than 80%?

Let us assume that the max marks are 50,50,100 and 100 resp.
total marks are : 80% of 300 i.e. 240
now divide 300 in ratio 4:8:13:15 such that the sum is 240.
marks are 24:48:78:90.
marks more than 80% in 02 subjects

His maximum marks would be a multiple of 6. Let it be 6x. So sum of his marks would be .8*6x = 4.8x. To simplify calculations multiply both sides by 100 so we get, max marks = 600x, His marks = 480x. Now subject wise his marks would be, 48,96,156, 180. Maximum marks in these respective subjects would be 100, 100, 200, 200. So his marks are 48/100, 96/100, 156/200, 180/200. Thus in 2 subjects he had greater than 80%.

2 subject