If you mean three fourths then it is not equivalent to seven eighths
seven eights is greater
seven eights is more than three fourths
seven eights. 1 half = 4 eights add 3 eights and you get 7 eights.
Seven eights plus three eights is ten eights. Now, possibly you intended to ask about eighths, rather than eights. Ten eighths is equal to one and a quarter. However, ten eights is equal to 80. The extra h makes a difference.
.75 or three-forths