Johnny was buying a limited editions Xbox one S. the price was $420 he has already payed 40% of the cost. How much does he still have to pay
He's already paid 40%, and 40% of $420 is 0.4 * 420 = 4 * 42 = 160 + 8 = 168
Johnny has so far paid $168, so he staill has yet to pay $420 - $168 = $320 - $68 = $260 - $8 = $252
Answer: Johnny still has to pay $252