HELP WITH THIS MATHS QUESTION PLEASE

[sturdy ingot]

HELP

[austere wing]

a) for 5<x<=10, could be 6 (3 times)
for 10<x<=15, it's a subset of 7<=x<=18
for 15<x<=20, could be 19 (7 times)
hence the minimum is 8 hikers
b) for 5<x<=10, could be 7 (3 times)
for 10<x<=15, it's a subset of 7<=x<=18
for 15<x<=20, could be 18 (7 times)
hence the maximum is just simply the sum:
3+8+7 = 18 hikers

[sturdy ingot]

@austere wing last one please I need to submit it quickly deadline is in an hour

[austere wing]

this is a similar question
try to do it yourself

[sturdy ingot]

Trust me I have

[sturdy ingot]

Please just one more time

I’m begging u

[austere wing]

a) 7 hikers
b) 4+7+6 = 17 hikers

[sturdy ingot]

Thank you so much