Home / 614.12-921.90-431

Finding the Fourth Proportional to 614.12, 921.90 and 431

Calculator

Solution

The fourth proportional to 614.12, 921.90 and 431 is: 647.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    614.12 : 921.90 = 431 : x
  2. Step 2: Convert to fraction form
    614.12/921.90 = 431/x
  3. Step 3: Cross multiply
    614.12x = 921.90 × 431
  4. Step 4: Simplify right side
    614.12x = 397,338.90
  5. Step 5: Solve for x
    x = 397,338.90/614.12
  6. Step 6: Final answer
    x = 647.01

Related Problems

Find fourth proportional to 307.06, 460.95 and 215.50
Half scale
Find fourth proportional to 1,228.24, 1,843.80 and 862
Double scale
Find fourth proportional to 615.12, 923.40 and 432
Similar ratio
Find fourth proportional to 921.18, 1,382.85 and 646.50
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.