In Goshawk-Eurasian nature reserve 30 percent of the birds are Hawks, and 40 percent of the non-Hawks are Paddyfield-Warblers. If there are 25 percent as many Kingfishers as Paddyfield-Warblers in the reserve, then what percent of the birds R in the nature reserve are not Hawks, Paddyfield-Warblers, or Kingfishers?  Pick:  A) 25%  B) 35%  C) 45%  D) 70%  E) 80%
1. We are given the following percentages: 30 (70), 40 (60), 25 (75). There are two threads from here. First starts at 30% and finishes there. Second one starts at 70, then 40, and then 25. We need a value that is divisible by 7, 2, and 5 at least once. lets pick a number now, say 700. So say if Non Hawks are 700 (this is 70% of the total, so total = 1000), then Paddy Warbs are 2/5 x 700 = 1400/5= 
<gadget id="calculator">1400/5</gadget>
<output>280</output>
280. Kingfishers, therefore, are   280/4= 
<gadget id="calculator">  280/4</gadget>
<output>70</output>
70. Lets add them up. 300 hawks + 280 Peddy Warbs + 70 kingsifhers= 650. So all others are  1000 - 650= 
<gadget id="calculator"> 1000 - 650</gadget>
<output>350</output>
350 or 35% of total birds.   The main job here to to identify the smart number to start the question with. This can be time consuming, but once identified, this question can be solved fairly quickly.   2. Another method: If X is total --&gt; Non Hawks= 0.7X --&gt; Warbs = 0.4(0.7X) --&gt; KFs = 0.25(0.4(0.7X)).   Our job is to find out R: (0.3X + 0.28X + 0.07X)/ X. OR 0.65X/X = 0.65. We need to find   1-0.65= 
<gadget id="calculator">  1-0.65</gadget>
<output>0.35</output>
0.35 or 35%.35%
<result>B</result>
In Goshawk-Eurasian nature reserve 30 percent of the birds are Hawks, and 40 percent of the non-Hawks are Paddyfield-Warblers. If there are 25 percent as many Kingfishers as Paddyfield-Warblers in the reserve, then what percent of the birds R in the nature reserve are not Hawks, Paddyfield-Warblers, or Kingfishers?