Answer: 22 miles
Explanation: Ms. G and Ms. Leahman both bike the same amount on Saturday:
4 miles to go to the city;
2 miles with Mr. Adams;
4 miles back to Bedstuy;
Then, both biked:
4 + 2 + 4 = 10 miles
Now, Mr. Adams bikes:
5 miles to go to the city;
2 miles together with the other two;
5 miles back to Bedstuy;
Then, he biked, in total:
5 + 2 + 5 = 12miles
So, the three of them biked, in total:
10 + 12 = 22
On Saturday, Ms. G, Mr. Adams and Ms. Leahman biked, in total, 22 miles.