$ time units -v '2 feet + 2 meters' feet 2 feet + 2 meters = 8.5616798 feet 2 feet + 2 meters = (1 / 0.11679951) feet real 0m0.009s user

$ time units -v '2 feet + 2 meters' feet 2 feet + 2 meters = 8.5616798 feet 2 feet + 2 meters = (1 / 0.11679951) feet real 0m0.009s user 0m0.005s sys 0m0.004s