Simplify the following text for a Grade 8 native English-speaking person.
Original: In 1856 , the Great Trigonometric Survey of British India established the first published height of Everest , then known as Peak XV , at 29002 f. In 1865 , Everest was given its official English name by the Royal Geographical Society upon recommendation of Andrew Waugh , the British Surveyor General of India at the time , who named it after his predecessor in the post , and former chief , Sir George Everest .
Simplified: This first published height was . Everest was given its official English name in 1865 by the Royal Geographical Society .