Given that 1/f = 1/u + 1/v , express u in terms of v and f

u = fv/(v - f)

Step-by-step explanation:

1/f = 1/u + 1/v

1/u = 1/f - 1/v = v/fv - f/fv = (v-f)/fv

1/u = (v-f)/fv

u = fv/(v - f)

b) 1/3 * 1/5

step-by-step explanation:

each smallest part is 1/15 since the written one is 1/5 and it's divided by 3 equal parts. (1/5 )/3 = 1/15 = 1/3 * 1/5

10.416 meters per second

step-by-step explanation:

distance=1 00 meters

time= 9.6 seconds in decimal form or 9 3/5 as a mixed number

average speed= 100/9.6

=10.416 meters per second or 10 52/125 as a mixed number.