Home / 755.40-1,131.42-430.56

Finding the Fourth Proportional to 755.40, 1,131.42 and 430.56

Calculator

Solution

The fourth proportional to 755.40, 1,131.42 and 430.56 is: 644.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    755.40 : 1,131.42 = 430.56 : x
  2. Step 2: Convert to fraction form
    755.40/1,131.42 = 430.56/x
  3. Step 3: Cross multiply
    755.40x = 1,131.42 × 430.56
  4. Step 4: Simplify right side
    755.40x = 487,144.20
  5. Step 5: Solve for x
    x = 487,144.20/755.40
  6. Step 6: Final answer
    x = 644.88

Related Problems

Find fourth proportional to 377.70, 565.71 and 215.28
Half scale
Find fourth proportional to 1,510.80, 2,262.84 and 861.12
Double scale
Find fourth proportional to 756.40, 1,132.92 and 431.56
Similar ratio
Find fourth proportional to 1,133.10, 1,697.13 and 645.84
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.