Inflation has a positive effect on exports and unemployment in most cases. It may improve the current account balance.

Inflation has a negative effect on interest rates and investments generally. High inflation rates increase heavily the interest rates and also decrease the number and value of feasible investment projects. As banking lend money they need to recuperate the same purchasing power in the future, also with a profit. Inflation forces them to increase the interest rate to compensate.

Regarding petrol, if inflation happens in the exporting country it may reduce the costs allowing for a decrease in price of oil or keep the oil companies sustainable at lower oil prices.

According to the Fisher hypothesis, the expected inflation is the main determinant of interest rates. It postulates that the nominal interest rate consists of an expected ‘real’ rate plus an expected inflation rate. Accordingly, a one-to-one relationship between inflation and interest rates is implied. Nevertheless, this hypothesis also suggests that real interest rates are unrelated to the expected rate of inflation and are determined entirely by the real factors (e.g. the productivity of capital and investor time preference).

For more details, please navigate to the following links.

http://globalbizresearch.org/economics/images/files/90464_JEIEFB_Johannes%20Peyavali%20Sheefeni%20Sheefeni.pdf

http://www.ccsenet.org/journal/index.php/ijef/article/viewFile/52565/29441

You can also benefit from the following thesis

http://allthesisonline.com/wp-content/uploads/2015/08/The-Relationship-Between-Interest-Rates-And-Inflation-In-South-Africa-Revisiting-Fisher%E2%80%99s-Hypothesis.pdf

Dear Sayed Mohammad Tariq Zafar 

Greetings,

Please find the attached file very related to your topic and may be answer your question ,

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