Answer:
36.4%
Explanation:
You know the most about Kim and Molly, so you should start with them.
Let kim's share = x
Therefore Molly's share = x + 105
Ratio
Kim is to Molly as 2 is 5
2/5 = x / (x + 105)
Solution
Cross multiply
2(x + 105) = 5x Remove the brackets.
2x + 2*105 = 5x Consolidate.
2x + 210 = 5x Subtract 2x from both sides
2x - 2x + 210 = 5x - 2x Reduce like terms.
210 = 3x Divide by 3
210/3 = x
70 = x
Laura's Share.
Kim = x = 70
Molly = x + 105 = 70 + 105 = 175
Kim + Molly + Laura = 385
70 + 175 + Laura = 385 Combine the left side
245 + Laura = 385 Subtract 245 from both sides
Laura = 385 - 245 Combine the right. (Subtract)
Laura = 140
Laura's %
Laura's % = (140 / 385) * 100 = 36.4 to 3 places.