Christina estimated 188% of 91 by performing these steps. What did she do wrong?

(90) (190 percent) = (90) (100 percent + 90 percent) = (90) (100 percent) + (90) (90 percent) = (90) (1.0) + (90) (0.9) = 90 + 18 = 108.
She rounded 188% up to 190%.
She rounded 91 down to 90.
She incorrectly broke 190% into 100 percent + 90 percent.
She incorrectly multiplied 90 and 0.9.