Answer:
There are 4 possible ways
Step-by-step explanation:
Data provided in the question:
Alex can hop in 1 steps, 2 steps, or 3 steps at a time.
From the above data it can be concluded that at a single maximum 3 steps can be run at a time
thus,
for running 3 steps at a time from the above data, we can have
with 1 step only : {1 , 1 , 1}
with 1 step first and 2 steps : {1 , 2}
with 2 steps first and then the 1 step: {2 , 1}
and 3 steps at once : {3}
thus, we have 4 possible ways to run up the stairs keeping the above condition.
