Solution:
Let Party A and Party B deposit in 3 yuan and 4 yuan respectively in February,
(3X+300)/(4X+500)=5/7,X=400。
Therefore, A's deposit in February is 3x= 1200 yuan, and B's deposit in February is 4x= 1600 yuan.
A: Omit.
After pouring 1/3 from barrel A to barrel B, pouring 1/5 from barrel B to barrel A, there is 24 kilograms of oil in each barrel at this time. How many kilograms of oil are there in barrels A and B?
Solution: According to the meaning, the total amount of two barrels of oil =24*2=48 kg.
Let's assume that barrel A initially contains X kilograms of oil and barrel B contains (48-X) kilograms.
Then 2x/3+(1x/3+48-x)/5 = 24;
8X/ 15+48/5 = 24;
The solution is X=27.
48-X=48-27=2 1 Answer: The two barrels of oil originally contained 27kg and 2 1 kg respectively.