Question 96444
{{{(75+63+68+x)/4>=70}}}
(206+x)/4>=70
51.5+.25x>=70
subtract 51.5 from both sides. .25x>=18.5
divide both sides x>=74 
Sam must get a grade greater than or equal to a 74 in order to get a 70 average.
Check:
75+63+68+74/4=70