Complete question :
Xavier is roller skating at 14 km/h and tosses a set of keys forward on the ground at 8 km/h. The speed of the keys relative to the ground is km/h.
Answer:
22 km/hr
Explanation:
Speed of keys with respect to ground ; V(k - g)
Speed of keys with respect to skater ; V(k - s)
Speed of skater with respect to ground ; V(s - g)
V(s - g) = 8 km/hr
V(k - s) = 14 km/hr
Substituting the values into the equation :
V(k - g) = V(s - g) + V(k - s)
V(k - g) = 8km/hr + 14km/hr
V(k - g) = 22 km/hr