To determine
To find:
How fast is the water skier rising as she leaves the ramp
Answer
The rate of rising of the water skier is 7.7 ft /s
Explanation
1. Formula:
Constant multiple rule:
ddxCf(x)=Cddx(fx)
2. Given:

dzdt=30 ft/s
3. Calculation:
By using the Pythagorean Theorem
Z2 = 152 + 42 = 225 + 16 = 241
Therefore, Z= 241
By using similar triangle property
y4=z241
⇒y=4z241
Differentiate with respect to t
dydt=ddt(4z241)
By using constant multiple rule
dydt=4241dzdt
Since, dzdt=30
dydt=4241*30
dydt=7.7
Conclusion:
Therefore, the rate of rising of the water skier is 7.7 ft /s