Answer:
79
Step-by-step explanation:
Let last test score be y
Average = sum of test scores/ number of test scores.
Average was given in question = 86
86= 70+85+95+93+94+y/6
86= 437+y/6
Cross multiply
86*6 =437+y
516= 437+y
Collect like terms
516-437=y
Y=79
