manny hiked 6 2/5 miles along a mountain trail. he stopped to climb a lookout tower 1/4 of the way along his hike. how many miles did manny hike before he stopped to climb the lookout tower?

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of