Home / 875.79-1,312.59-486

Finding the Fourth Proportional to 875.79, 1,312.59 and 486

Calculator

Solution

The fourth proportional to 875.79, 1,312.59 and 486 is: 728.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    875.79 : 1,312.59 = 486 : x
  2. Step 2: Convert to fraction form
    875.79/1,312.59 = 486/x
  3. Step 3: Cross multiply
    875.79x = 1,312.59 × 486
  4. Step 4: Simplify right side
    875.79x = 637,918.74
  5. Step 5: Solve for x
    x = 637,918.74/875.79
  6. Step 6: Final answer
    x = 728.39

Related Problems

Find fourth proportional to 437.90, 656.30 and 243
Half scale
Find fourth proportional to 1,751.58, 2,625.18 and 972
Double scale
Find fourth proportional to 876.79, 1,314.09 and 487
Similar ratio
Find fourth proportional to 1,313.69, 1,968.89 and 729
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.