Answer:
By the early 1900s, the alliances had developed. The Dual Alliance had become the Triple Alliance with Italy (although Italy stayed out of the war in 1914).
In 1907, Britain joined Russia and France to form the Triple Entente. Britain was much less committed to this alliance than Russia or France.
Explanation:
Great Britain joined in fighting in WWI because they were apart of the alliance and by joining would help boost their economy
