In a computer class 40 students 60% are boys 25% of the boys and 50% of the girls are using portable computers the rest are using desktop computers how many students are using desktop computers

If 60 percent are boys, than there are 24 boys since 0.6 * 40 = 24. There are also 16 girls since 40 - 24 = 16. If 25 percent of the boys are using portables, than 24 * 0.25 = 6 boys are using portables. If 50 percent of the girls are using portables than 16 * 0.5 = 8 girls are using portables. Therefore, 6 + 8 = 14 people are using portables. Since we are looking for how many are using desktops, we do 40 - 14 to get that 26 kids are using desktops.