Home / 1,005-1,507.86-321

Finding the Fourth Proportional to 1,005, 1,507.86 and 321

Calculator

Solution

The fourth proportional to 1,005, 1,507.86 and 321 is: 481.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,005 : 1,507.86 = 321 : x
  2. Step 2: Convert to fraction form
    1,005/1,507.86 = 321/x
  3. Step 3: Cross multiply
    1,005x = 1,507.86 × 321
  4. Step 4: Simplify right side
    1,005x = 484,023.06
  5. Step 5: Solve for x
    x = 484,023.06/1,005
  6. Step 6: Final answer
    x = 481.61

Related Problems

Find fourth proportional to 502.50, 753.93 and 160.50
Half scale
Find fourth proportional to 2,010, 3,015.72 and 642
Double scale
Find fourth proportional to 1,006, 1,509.36 and 322
Similar ratio
Find fourth proportional to 1,507.50, 2,261.79 and 481.50
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.