Math Problem Statement

Solve the problems related to expressions, fractions, and equations shown in the uploaded image.

Solution

Let's break this down step-by-step to solve each problem from your image:


Problem 9: Which expressions are equivalent to -3 - (7.5 + 4)? Select all that apply.

We start with the expression: 3(7.5+4)-3 - (7.5 + 4) First, simplify the parentheses: 7.5+4=11.57.5 + 4 = 11.5 Then: 311.5=14.5-3 - 11.5 = -14.5

Now, let's analyze the given answer options:

  • A. (7.5 + 4) - 3:
    This simplifies to 11.53=8.511.5 - 3 = 8.5, which is NOT equivalent to 14.5-14.5.

  • B. -7.5 + 4 - 3:
    Simplify step-by-step: 7.5+4=3.5-7.5 + 4 = -3.5 3.53=6.5-3.5 - 3 = -6.5 This is NOT equivalent to 14.5-14.5.

  • C. -(7.5 + 4) + 3:
    Simplify the parentheses first: (7.5+4)=11.5-(7.5 + 4) = -11.5 Then: 11.5+3=8.5-11.5 + 3 = -8.5 This is NOT equivalent to 14.5-14.5.

  • D. -3 - (4 + 7.5):
    Simplify the parentheses: 4+7.5=11.54 + 7.5 = 11.5 311.5=14.5-3 - 11.5 = -14.5 This is EQUIVALENT to 14.5-14.5.

  • E. -(3 - 7.5) + 4:
    Simplify inside the parentheses: 37.5=4.53 - 7.5 = -4.5 (4.5)=4.5-(-4.5) = 4.5 4.5+4=8.54.5 + 4 = 8.5 This is NOT equivalent to 14.5-14.5.

  • F. -3 + -(7.5 - 4):
    Simplify inside the parentheses: 7.54=3.57.5 - 4 = 3.5 3+3.5=6.5-3 + -3.5 = -6.5 This is NOT equivalent to 14.5-14.5.

  • G. -3 - (7.5 + 4):
    This is the original expression, and it simplifies to 14.5-14.5, so it is EQUIVALENT.

Correct answers:
D and G


Problem 10: Which expression is equivalent to 5+2135 + 2 \frac{1}{3}?

Convert 2132 \frac{1}{3} into an improper fraction: 213=732 \frac{1}{3} = \frac{7}{3}

Then: 5+213=5+735 + 2 \frac{1}{3} = 5 + \frac{7}{3} Convert 5 into a fraction with a denominator of 3: 5=1535 = \frac{15}{3} Add the fractions: 153+73=223\frac{15}{3} + \frac{7}{3} = \frac{22}{3}

Now, match the options:

  • A. 5+2135 + 2 \frac{1}{3}: Matches directly.
  • B. 157315 - \frac{7}{3}: Simplifies to 152.33315 - 2.333, which is incorrect.
  • C. 1022310 - 2 \frac{2}{3}: Converts to 108310 - \frac{8}{3}, which is incorrect.
  • D. 223\frac{22}{3}: Matches the equivalent fraction form.

Correct answers:
A and D


Problem 11: Select the correct number from each list to complete the equation.

Given: 78(2+34)=(something)+78\frac{7}{8} - \left(2 + \frac{3}{4}\right) = \text{(something)} + \frac{7}{8}

Simplify 2+342 + \frac{3}{4}: 2=84,2+34=84+34=1142 = \frac{8}{4}, \quad 2 + \frac{3}{4} = \frac{8}{4} + \frac{3}{4} = \frac{11}{4}

Now subtract: 78114\frac{7}{8} - \frac{11}{4} Convert 114\frac{11}{4} to have a denominator of 8: 114=228\frac{11}{4} = \frac{22}{8} 78228=158\frac{7}{8} - \frac{22}{8} = \frac{-15}{8}

The equation becomes: 158=(something)+78\frac{-15}{8} = \text{(something)} + \frac{7}{8} Subtract 78\frac{7}{8} from both sides: 15878=228\frac{-15}{8} - \frac{7}{8} = \frac{-22}{8}

Now match the correct numbers from the list: 2and34\boxed{-2 \, \text{and} \, -\frac{3}{4}}


Do you want further clarification? Let me know!

Here are 5 related questions for deeper practice:

  1. How do you simplify expressions with parentheses and negatives?
  2. How do you convert mixed numbers to improper fractions?
  3. How can you combine like terms with fractions?
  4. What is the process for solving subtraction with fractions?
  5. How do you identify equivalent expressions in multiple-choice questions?

Tip: Always simplify step-by-step and carefully check signs when working with negatives.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Arithmetic operations with negative numbers
Simplifying expressions
Converting mixed numbers to improper fractions
Solving equations involving fractions

Formulas

a - (b + c) = a - b - c
Converting mixed numbers: a b/c = (a*c + b)/c
Addition and subtraction of fractions with a common denominator

Theorems

Properties of arithmetic with negative numbers
Equivalence of expressions

Suitable Grade Level

Grade 7