Analysis: original profit is 0.2 = (0.8d-a)/a-> A=2D/3.
The current profit is 0.25 = (0.75d-b)/b-> B=3D/5.
(A-B)/A = 1/ 10 = 10%
2. The working speeds of Party A and Party B are set to V 1 and V2 (pieces/hour) respectively. There are x parts in this batch.
There is X=V 1*(t+2)=4V2*t/5(t is * * * and can be expressed by 1 in time).
x = 150+v 1 * t-90 = 4v 2 * t/5-& gt； x = v 1 * t+600 = 4v 2 * t/5-& gt； If V 1=300, V2= 1 125 (because the efficiency is four fifths of that of A, the output per hour is 900). Conclusion: B makes V2= 1 125 pieces/hour.
3,
After moving 1 time, A: A-B: B+B (moving out of A)
After moving twice, A: A-B+(A-B) = 2A-2B B: B+B-(A-B) = 3B-A (deleted from B)
After moving for three times, A: 2A-2B-(3B-A) = 3A-5B: 3B-A+(3B-A) = 6B-2A (moving out of A)
After moving for four times, A: 3a-5b+(3a-5b) = 6a-10bb: 6b-2a-(3a-5b) =11b-5a (removed from B).
After moving for five times, a: 6a-10b-(110b-5a) =110a-210b:1/kloc-.
After finding the law, the result is:11a-21b = 22b-10a = "21a = 43 yin130.
2730 & lt2 1 A
A/B = 43 * n/2 1 (the ratio n can be drawn from 1 to the fifth generation).
The volume of a cubic iron block with a length of 4.6 decimeters is V 1=6*6*6=2 16. The volume of aquatic plants V=24*9*8= 1728.
Injection water volume V2=24*9*4=869 (useless in the title) Rising height H=V 1/(24*9)= 1 Remarks (unit omitted).
Analysis: the volume of iron block is the volume of water rising, and the height of water rising is divided by the bottom area.
5. Using Pythagorean theorem, we know that AC=5, because point A and point C coincide, and d is the midpoint of AC. If AD=CD=2.5, we can prove that triangle ADE is equal to triangle CDE, and CE=AE ED is perpendicular to AC.
Let BE=x have CE=4-x from ab * ab+be * be = AE * AE = ad * ad+de * de = > 9+x * x = AE * AE = 6.25+de * de.
If CE=AE=(4-x), then (4-x)*(4-x)=9+x*x, and x=7/8. Using the equilateral triangle theorem, DE * DE = CE * CE-CD * CD = 625/64-25/4 = 225/64 = DE =15/8.
Quadrilateral area ABED = triangle area ABE+ triangle area ade = 0.5 * be * ab+0.5 * de * ad = 0.5 * 7/8 * 3+0.5 *15/8 * 2.5 =10.5/8+/kloc-0.
= 1 17/32
There are too many questions, some of which are not detailed enough.