1) There were a total of 840 guests at a wedding dinner. 60% of them were adults, and the rest were children. Some boys left before the dessert was served. As a result, the percentage of adults increased to 70%. How many boys left before the dessert was served?
I got 120
120
Adults = .6 * 840 = 504
children = .4 * 840 = 336
504 = .7 (840 - boys)
252
I got 84.
840*.60=504
840*.70=588
588-504=84 boys.