Respuesta :

Multiply 100 times 5 in your head to get 500, 

100 * 5 = 500
90 * 5 = 450
8 * 5 = 40
Put those 3 together into one equation, \/
(100 * 5) + (90 * 5) + (8 * 5) = 990 OR (100 * 5) + (98 * 5) = 990
depends on how distributed the teacher wants it to be.