devaughn,sageis2timessydneysage,thesumoftheiragesis78,whatissydneysage

devaughn,sageis2timessydneysage,thesumoftheiragesis78,whatissydneysage

Let d be Devaughn's age. Let s be Sydney's age. We have two equations:

1. d = 2s
2. d + s = 78

Substitute (1) into (2)
2s + s = 78
3s = 78

Entering 3x = 78 into the search engine, we get s = 26.