What was the TV commercial in the 1970's where a group of people sang a song for Pepsi?

I may be mistaken (as I was not even born until 1983), but I don't believe Pepsi had a commercial like that in the 1970s. In the 1970s, Pepsi's main marketing campaign was the "Pepsi challenge," where people would be given a blind taste test between Pepsi and Coke. Because Pepsi is slightly sweeter, it always won these tests.

Coca-Cola had an ad campaign in the seventies, which sounds very similar to what you're describing. It featured a group of young people standing on a grassy hill in a field, singing the song "I'd Like to Teach the World to Sing," with altered lyrics that were about Coca-Cola: "I'd like to buy the world a Coke, and keep it company..."

Pepsi did have a couple of Commercial Jingles in the seventies, but to my knowledge, none of them were a full song, like the Coca-Cola "I'd Like to Buy the World a Coke" song, and none of the commercials featured a group of people standing around singing the jingle.

The jingles were: "You've Got a Lot to Live, and Pepsi's Got a Lot to Give" (1969 - 1975), "Have a Pepsi Day," (1975 - 1977), and "Join the Pepsi People (Feeling Free)" (1977 - 1980).

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