Not my work but found answer key to answer u need.
Answer:
t_a = 7 s
t_w = 5 s
Step-by-step explanation:
Given:
- The average speed in air v_a = 16 m/s
- The average speed in water v_w = 3 m/s
- The total distance D = 127 m
- The total time T = 12 s
Find:
How long did the stone fall in air and how long did it fall in the water?
Solution:
- Lets time taken by stone to drop through air as t_a = t_a.
- The time taken in water would be t_w = (12 - t_a)
- The total distance covered can be calculated as:
D = v_a*t_a+ v_w*(12 - t_a)
127 = 16*t_a + 3*(12 - t_a)
Simplify and solve for t:
91 = 16*t_a - 3t_a
13*t_a = 91
t_a = 7 s
t_w = 5 s
Answer:
C
Step-by-step explanation:
Answer:
x = 5/(10 - a - b)
Step-by-step explanation:
Solve for x:
4 + 3 x - a x = 9 - 7 x + b x
Collect in terms of x:
x (3 - a) + 4 = 9 - 7 x + b x
Collect in terms of x:
x (3 - a) + 4 = x (b - 7) + 9
Subtract (b - 7) x + 4 from both sides:
x (10 - a - b) = 5
Divide both sides by 10 - a - b:
Answer: x = 5/(10 - a - b)
Answer:
3. It's b and c 4. total number of participants in marathon=99+121=220 percentage of female = 121/220×100 =55% 5. the answer is 7
Step-by-step explanation:
