Is depositing an amount of 100,000 in an investment certificate with a 15% monthly interest rate for 3 years, with the possibility of taking a loan guaranteed by this certificate for 90,000 EGP at an 11% interest rate to be paid in installments, considered usury (riba)?

The bank in question is usurious, as it offers a fixed, guaranteed interest rate in exchange for the investment certificate. Therefore, it is not permissible to deal with it or borrow from it with interest, for all of that is usury, and it is among the gravest of prohibitions. Allah Almighty said: "O you who have believed, fear Allah and give up what remains [due to you] of interest, if you should be believers. And if you do not, then be informed of a war [against you] from Allah and His Messenger."