Bank X pays a simple interest of TaKa 80 on principal o taka 1,000 annually . Bank y pays a simple interest of TaKa 140 on a principal of Taka 1000 annually . What is the ratio of the interest rates of Bank x to Bank y ?
ক) 4:7
খ) 6:8
গ) 9:18
ঘ) 2:7
