1. Problem: Find the percent increase in the number of pupils from 25 to 32. Step 1: Calculate the increase: $32 - 25 = 7$ Step 2: Use the percent increase formula: $\left(\frac{\text{increase}}{\text{original}}\right) \times 100 = \left(\frac{7}{25}\right) \times 100 = 28\%$ Answer: C. 28% 2. Problem: Find the percent markup from 6400 to 6600. Step 1: Calculate the increase: $6600 - 6400 = 200$ Step 2: Calculate percent markup: $\left(\frac{200}{6400}\right) \times 100 = 3.125\%$ Answer: A. 3.125% 3. Problem: Find the percent of new members joining a basketball club increasing membership from 50 to 60. Step 1: Calculate increase: $60 - 50 = 10$ Step 2: Percent increase: $\left(\frac{10}{50}\right) \times 100 = 20\%$ Answer: C. 20% 4. Problem: Compute percent increase in Ellecon's Math test marks from 72 to 90. Step 1: Increase: $90 - 72 = 18$ Step 2: Percent increase: $\left(\frac{18}{72}\right) \times 100 = 25\%$ Answer: D. 25% 5. Problem: School enrollment increased from 240 to 261. Step 1: Increase: $261 - 240 = 21$ Step 2: Percent increase: $\left(\frac{21}{240}\right) \times 100 = 8.75\%$ Answer: B. 8.75% 6. Problem: Percent decrease in Math Club membership from 80 to 56. Step 1: Decrease: $80 - 56 = 24$ Step 2: Percent decrease: $\left(\frac{24}{80}\right) \times 100 = 30\%$ 7. Problem: Percent decrease in company employees from 75 to 60. Step 1: Decrease: $75 - 60 = 15$ Step 2: Percent decrease: $\left(\frac{15}{75}\right) \times 100 = 20\%$ 8. Problem: Percent decrease in skirt price from 240 to 204. Step 1: Decrease: $240 - 204 = 36$ Step 2: Percent decrease: $\left(\frac{36}{240}\right) \times 100 = 15\%$ 9. Problem: Daily sales diminished from 15000 to 12450. Step 1: Decrease: $15000 - 12450 = 2550$ Step 2: Percent decrease: $\left(\frac{2550}{15000}\right) \times 100 = 17\%$ 10. Problem: Price of mango dropped from 120 to 90. Step 1: Decrease: $120 - 90 = 30$ Step 2: Percent decrease: $\left(\frac{30}{120}\right) \times 100 = 25\%$