1. Problem 9: A clock loses 18 seconds every hour. It was set correctly at 8:00 am Monday. Find the time the clock shows at 11:20 am Saturday. 2. Calculate total hours from 8:00 am Monday to 11:20 am Saturday. Monday 8:00 am to Saturday 8:00 am = 5 days = $5 \times 24 = 120$ hours From 8:00 am to 11:20 am Saturday = 3 hours 20 minutes = $3 + \frac{20}{60} = 3.333$ hours Total time elapsed = $120 + 3.333 = 123.333$ hours 3. Calculate total seconds lost by the clock. Loss per hour = 18 seconds Total loss = $18 \times 123.333 = 2220$ seconds Convert seconds lost to minutes: $\frac{2220}{60} = 37$ minutes 4. Calculate the time shown by the clock. Actual time elapsed = 123 hours 20 minutes Clock loses 37 minutes, so clock time elapsed = $123.333 - 0.617 = 122.716$ hours Convert 0.716 hours to minutes: $0.716 \times 60 = 43$ minutes Clock time elapsed = 122 hours 43 minutes Add this to 8:00 am Monday: 8:00 am + 122 hours 43 minutes = 5 days 2 hours 43 minutes later 5 days from Monday 8:00 am is Saturday 8:00 am Add 2 hours 43 minutes: Saturday 10:43 am Answer: The clock will read 10:43 am on Saturday. --- 1. Problem 10: Complete triangle ABC with AB = 5 cm, BC = 10 cm, and angle BAC = 120°. Measure angle ABC. 2. Using ruler and compass: - Draw AB = 5 cm. - At point A, construct a 120° angle. - From point B, draw an arc with radius 10 cm. - The intersection of the 120° ray from A and the arc from B is point C. 3. Connect points B and C to complete triangle ABC. 4. Measure angle ABC using a protractor. Answer: The size of angle ABC is approximately 30°. --- 1. Problem 11: Shopkeeper sells item for 2740 with profit 3x, and for 2340 with loss 2x. Find cost price. 2. Let cost price = $P$. Profit case: $2740 = P + 3x$ Loss case: $2340 = P - 2x$ 3. Subtract second from first: $2740 - 2340 = (P + 3x) - (P - 2x) \Rightarrow 400 = 5x \Rightarrow x = 80$ 4. Substitute $x=80$ into profit case: $2740 = P + 3(80) = P + 240 \Rightarrow P = 2740 - 240 = 2500$ Answer: The shopkeeper paid 2500 for the item.