Answer:
40%
Step-by-step explanation:
Devana owns 40% of GW Corp. despite having another 40% shares in Alpine Inc. This is as a result of Devana not having up to 50% shares in Alpine Inc.
Without up to 50% shares in Alpine Inc, the shares of Alpine Inc. in GW Corp. cannot be attributed to Devana.
This means that for Devana to own Alpine Inc shares in GW Corp. it has to acquire 10% more in addition to the 40% it already has.
Cheers.