Current location - Training Enrollment Network - Mathematics courses - The first math problem about interest rate, the specific steps should be set to X.
The first math problem about interest rate, the specific steps should be set to X.
1。 432*20%=86.4

2。 450/( 1-20%)=562.5 The pre-tax interest rate is 562.5 and the annual interest rate is 2.25%, so the principal is 562.5/2.25% = 25,000.

3。 The after-tax interest is 8 14.05-800= 14.05, and the pre-tax interest is14.05/(1-20%) =17.5625.

Interest rate:17.5625/800 = 2.195%.

4。 (536-500)/500= 7.2%

5。 2000*( 1+8.64%)=2 172.8

6。 (3243-3000)/3= 8 1, that is, the annual interest is 8 1 yuan. 8 1/3000=2.7%

7。 The pre-tax interest is 48.6/(1-20%) = 60.75/2 = 30.375, and the deposited money is 30.375/2.43%= 1250.