Home / 753.21-1,039.38-421.64

Finding the Fourth Proportional to 753.21, 1,039.38 and 421.64

Calculator

Solution

The fourth proportional to 753.21, 1,039.38 and 421.64 is: 581.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    753.21 : 1,039.38 = 421.64 : x
  2. Step 2: Convert to fraction form
    753.21/1,039.38 = 421.64/x
  3. Step 3: Cross multiply
    753.21x = 1,039.38 × 421.64
  4. Step 4: Simplify right side
    753.21x = 438,238.99
  5. Step 5: Solve for x
    x = 438,238.99/753.21
  6. Step 6: Final answer
    x = 581.83

Related Problems

Find fourth proportional to 376.61, 519.69 and 210.82
Half scale
Find fourth proportional to 1,506.42, 2,078.76 and 843.27
Double scale
Find fourth proportional to 754.21, 1,040.76 and 422.64
Similar ratio
Find fourth proportional to 1,129.82, 1,559.07 and 632.45
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.