The question consists of two parts: Part 1: Evaluate the expression $75.0785 - 34.624 + 9.83$ and round the result to two decimal places. Part 2: Given two sets $X = \{x: x < 7\}$ and $Y = \{y: y \text{ is a factor of } 24\}$ that are subsets of $\mu = \{1, 2, 3, ..., 10\}$, find the intersection of the two sets, $X \cap Y$.

ArithmeticArithmetic OperationsSet TheorySubtractionAdditionRoundingSet IntersectionFactors
2025/4/10

1. Problem Description

The question consists of two parts:
Part 1: Evaluate the expression 75.078534.624+9.8375.0785 - 34.624 + 9.83 and round the result to two decimal places.
Part 2: Given two sets X={x:x<7}X = \{x: x < 7\} and Y={y:y is a factor of 24}Y = \{y: y \text{ is a factor of } 24\} that are subsets of μ={1,2,3,...,10}\mu = \{1, 2, 3, ..., 10\}, find the intersection of the two sets, XYX \cap Y.

2. Solution Steps

Part 1:
First, perform the subtraction: 75.078534.624=40.454575.0785 - 34.624 = 40.4545.
Next, perform the addition: 40.4545+9.83=50.284540.4545 + 9.83 = 50.2845.
Finally, round the result to two decimal places: 50.284550.2850.2845 \approx 50.28.
Part 2:
First, define set X based on the given condition x<7x < 7 and the universal set μ\mu. X={1,2,3,4,5,6}X = \{1, 2, 3, 4, 5, 6\}.
Next, define set Y based on the condition that yy is a factor of 24 and the universal set μ\mu. The factors of 24 are 1, 2, 3, 4, 6, 8, 12, and
2

4. Since $Y$ is a subset of $\mu = \{1, 2, 3, ..., 10\}$, $Y = \{1, 2, 3, 4, 6, 8\}$.

The intersection of sets X and Y, XYX \cap Y, consists of elements that are in both X and Y.
XY={1,2,3,4,6}X \cap Y = \{1, 2, 3, 4, 6\}.

3. Final Answer

Part 1: C. 50.28
Part 2: B. {1, 2, 3, 4, 6}