ABBIX has a complex financial system with the following relationships: The ratio of required reserves to total deposits is 15 percent, and the ratio of noncheckable deposits to checkable deposits is 40 percent. In addition, currency held by the nonbank public amounts to 20 percent of checkable deposits. The ratio of government deposits to checkable deposits is 8 percent. Initial excess reserves are $900 million.

Assume that ABBIX has a target M1 money supply $2.8 billion. The only variable that you have direct control over is the required reserves ratio. What would the required reserves ratio have to be to reach the target M1 money supply amount? Assume the other original ratio relationships hold.