Stan and hilda can mow the lawn in 35 min if they work together. if hilda works twice as fast as stan, how long would it take stan to mow the lawn alone?

105 minutes "Stan and Hilda can mow the lawn in 35 min" 35 = 1/(S + H) "Hilda works twice as fast as Stan" H = 2S "how long would it take Stan to mow the lawn alone?" T = 1/S First, let's determine what S is, so 35 = 1/(S + H) Substitute 2S for H 35 = 1/(S + 2S) Solve for S 35 = 1/(3S) 35(3S) = 1) 105S = 1 S = 1/105 Now solve T = 1/S with S = 1/105 T = 1/S T = 1/(1/105) T = 1/1 / 1/105 T = 1/1 * 105/1 T = 105 So it will take Stan 105 minutes to mow the lawn alone.

Ithink it's the first one ( let me know if it right)