Answer :
90 Tv’s are high def! 300/100 = 3 (this is what 1% equals because there’s 100% total) so if we know 1% is 3 tv’s and 30% are high def, then we find out how many tv’s 30% is. so if 3 is 1% then 30 x 1= 30 then 30x3 = 90!