Need help with motion problem

[DrChaos]

I need help with this motion problem. It's in the Life of Fred: Beginning Algebra book. "It takes 175 seconds for S. Snow to walk from his room to the Waddle Doughnuts store on base. Going there, he walks at 3 ft/sec, and on the way back he zooms along at 4 ft/sec. How long did it take him to walk to the store? (Start by letting t = rhe time he took to walk to the store)".

I tried 3t + 2(4t) = 175 sec but that doesn't work

 

[Bob Brown MSEE]

I need help with this motion problem. It's in the Life of Fred: Beginning Algebra book. "It takes 175 seconds for S. Snow to walk from his room to the Waddle Doughnuts store on base. Going there, he walks at 3 ft/sec, and on the way back he zooms along at 4 ft/sec. How long did it take him to walk to the store? (Start by letting t = rhe time he took to walk to the store)".

I tried 3t + 2(4t) = 175 sec but that doesn't work

In this type of question, I like to draw a velosity vrs time graph.
Distance is the area between graph and t-axis.
Since the distance to store is the negative of the distance back.
So,
3*175 = 4x

Remember, total trip is x+175

PS. "to the store" is used twice, it is not clear when this phrase means round-trip.