Math Riddle. Any ideas?

Even if it’s been years since you were in school, refreshing your memory with a brain teaser can be fun and beneficial.

Test Your Math Skills

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Answer:

There are some answer on reddit

“7 – (log7(7) + log7(7))”

7-(log7/log√7)

7-log7(7*7)

“747%7

Where % is usually used for modulo. (Edit: At least in programming. Not too sure about maths.)
% is fine for modulo in math. I’ve more often seen it written out as mod though. Like 747 mod 7”

“7 / (.7 + .7) = 5”

“7 – 70 – 70 = 5”