In Yangzhou, Jiangsu, if the social security base is 9300, the tax deduction calculation involves several steps. First, calculate the amount of social security contributions deducted from your salary. The typical proportions for employees in Yangzhou are as follows: 8% for pension insurance (9300 * 0.08 = 744 yuan), 2% + 10 yuan for medical insurance (9300 * 0.02 + 10 = 196 yuan), 1% for unemployment insurance (9300 * 0.01 = 93 yuan), and 8% for housing provident fund (9300 * 0.08 = 744 yuan). In total, the social security and housing provident fund deductions amount to 744 + 196 + 93 + 744 = 1777 yuan.

Next, calculate the taxable income. The formula for taxable income is: taxable income = monthly income - 5000 yuan (tax threshold) - special deductions (social security and housing provident fund) - special additional deductions - other deductions determined by law. Assuming there are no special additional deductions and other deductions for simplicity, with a social security base of 9300 as the income, the taxable income is 9300 - 5000 - 1777 = 2523 yuan.

Finally, calculate the tax amount. According to the individual income tax rate table for wages and salaries in China, for taxable income within the range of 0 - 3000 yuan, the tax rate is 3% and the quick - deduction amount is 0. So the tax amount is 2523 * 0.03 - 0 = 75.69 yuan.

In summary, when the social security base in Yangzhou, Jiangsu is 9300, assuming no special additional deductions and other deductions, the approximate amount of tax deducted is 75.69 yuan. However, if there are special additional deductions such as for housing loans, children's education, etc., the actual tax amount will be adjusted accordingly.