1. Problem 1: Ike and Seb's soft drink sharing.
Let Ike originally have $x$ ml and Seb have $120 - x$ ml.
Step 1: Dad pours one-third of Ike's drink into Seb's glass.
Ike now has $x - \frac{x}{3} = \frac{2x}{3}$ ml.
Seb now has $120 - x + \frac{x}{3} = 120 - \frac{2x}{3}$ ml.
Step 2: Dad pours one-third of Seb's drink back into Ike's glass.
One-third of Seb's current drink is $\frac{1}{3} \times \left(120 - \frac{2x}{3}\right) = 40 - \frac{2x}{9}$ ml.
After pouring back:
Ike has $\frac{2x}{3} + 40 - \frac{2x}{9} = \frac{6x}{9} + 40 - \frac{2x}{9} = \frac{4x}{9} + 40$ ml.
Seb has $120 - \frac{2x}{3} - \left(40 - \frac{2x}{9}\right) = 120 - \frac{6x}{9} - 40 + \frac{2x}{9} = 80 - \frac{4x}{9}$ ml.
Step 3: They have equal amounts now, so:
$$\frac{4x}{9} + 40 = 80 - \frac{4x}{9}$$
Step 4: Solve for $x$:
$$\frac{4x}{9} + \frac{4x}{9} = 80 - 40$$
$$\frac{8x}{9} = 40$$
$$x = 40 \times \frac{9}{8} = 45$$
So Ike originally had 45 ml, Seb had $120 - 45 = 75$ ml.
Step 5: Find how much Ike's drink differs from Seb's:
$75 - 45 = 30$ ml, so Ike had 30 ml less than Seb.
Answer: (B) 少 30ml.
2. Problem 2: Hui's reading problem.
Let the total number of pages be $P$.
Step 1: First day, Hui reads $\frac{1}{5}P + 12$ pages.
Pages left after day 1:
$$P - \left(\frac{1}{5}P + 12\right) = \frac{4}{5}P - 12$$
Step 2: Second day, Hui reads $\frac{1}{4}$ of remaining pages plus 15 pages:
$$\frac{1}{4} \left(\frac{4}{5}P - 12\right) + 15 = \frac{1}{5}P - 3 + 15 = \frac{1}{5}P + 12$$
Pages left after day 2:
$$\left(\frac{4}{5}P - 12\right) - \left(\frac{1}{5}P + 12\right) = \frac{3}{5}P - 24$$
Step 3: Third day, Hui reads $\frac{1}{3}$ of remaining pages plus 18 pages:
$$\frac{1}{3} \left(\frac{3}{5}P - 24\right) + 18 = \frac{1}{5}P - 8 + 18 = \frac{1}{5}P + 10$$
Pages left after day 3:
$$\left(\frac{3}{5}P - 24\right) - \left(\frac{1}{5}P + 10\right) = \frac{2}{5}P - 34$$
Step 4: Given pages left for next day is 62:
$$\frac{2}{5}P - 34 = 62$$
Step 5: Solve for $P$:
$$\frac{2}{5}P = 96$$
$$P = 96 \times \frac{5}{2} = 240$$
Answer: (C) 240 pages.
Soft Drink Sharing Reading
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