Billionaire investor Rakesh Jhunjhunwala-backed low-cost airline Akasa Air said on Wednesday it signed an agreement with CFM International for its LEAP-1B engines in a deal valued at nearly $4.5 billion at list price to power the 737 MAX airplanes it recently bought.Mr Jhunjhunwala-backed Akasa Air had placed an order for 72 Boeing 737 MAX jets on Tuesday, valued at nearly $9 billion at list prices.