Home / 875.84-1,209.15-639.56

Finding the Fourth Proportional to 875.84, 1,209.15 and 639.56

Calculator

Solution

The fourth proportional to 875.84, 1,209.15 and 639.56 is: 882.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    875.84 : 1,209.15 = 639.56 : x
  2. Step 2: Convert to fraction form
    875.84/1,209.15 = 639.56/x
  3. Step 3: Cross multiply
    875.84x = 1,209.15 × 639.56
  4. Step 4: Simplify right side
    875.84x = 773,317.93
  5. Step 5: Solve for x
    x = 773,317.93/875.84
  6. Step 6: Final answer
    x = 882.94

Related Problems

Find fourth proportional to 437.92, 604.58 and 319.78
Half scale
Find fourth proportional to 1,751.69, 2,418.30 and 1,279.11
Double scale
Find fourth proportional to 876.84, 1,210.53 and 640.56
Similar ratio
Find fourth proportional to 1,313.76, 1,813.73 and 959.33
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.