1, discount

A few percent discount means a few tenths, that is, dozens of percent.

Current price = original price × discount.

Original price = current price ÷ discount.

Discount = current price ÷ original price.

2, become a number

Fraction means that one number is a fraction of another.

3. Tax rate

Tax rate = tax payable ÷ various incomes × 100%.

Taxable amount = income x tax rate.

All kinds of income = tax payable/tax rate.

4. Interest rate

Interest = principal × interest rate× deposit period.

Principal = interest/interest rate/deposit period.

Interest rate = interest/principal/deposit period.

Term = interest/principal/interest rate.

Sum of principal and interest = principal+interest.

Sum of principal and interest = principal ×( 1+ interest rate× deposit period).

5. Cylinder volume formula

Cylinder volume = bottom area × high V column =Sh=πr? h .

Height of cylinder = volume-bottom area h = V- bottom of column-s.

The bottom area of the cylinder = volume ÷ height ÷ S bottom =V column ÷ h.