Answer:
as we know Sara need 8 tube in 3 experiment
she will use 2 tube in 1 experiment
now she have 6 tube in other experiments
so the question said to find how many tube were used in both experiment equally so 3,3 test tube were needed for each of the other two experiment
Step-by-step explanation:
total tube=8 (3 experiment)
used =2tube (1 experiment)
remaining=8-2=6
now ,
dividing 6 into 2 equal part
so,=6/2=3
so 3 tube were used in 2nd experiment and 3in 3rd experiment
Recall your d = rt, distance = rate * time.
so, in his usual speed, say is hmm "r" mph, so in his usual "r" speed, he rolls on for the 48 miles and it takes him "t" hours to get there.
now, if he increases his speed by 2 mph, then his new speed is "r + 2", and he arrives there 4 hours earlier, so if he took "t" hours going at "r" speed, then when he's going faster at "r + 2", he only takes "t - 4" hours, for the same 48 miles.


it cannot be a negative value, since is just a forward speed rate, so can't be -6.