Answer:
20%
Step-by-step explanation:
150-120 is 30
30 is 1/5 of 150
1/5 is .2, which is 20%
Hope that helps~
Answer:


Step-by-step explanation:
Given


Solving (a): T7
Substitute 7 for n in 


Calculate S7 and S6



So:


Solving (b): Tn

Where 
Calculate
We have:

Open brackets



So:



Collect Like Terms


The sum means adding, so your answer is f + 6
6,051m = 6,000m + 51m
1km=1,000 metres
--------------------------------
Therefore:
6,051 metres = 6,000/1,000km + 51/1,000km
=6,051/1,000km
=6.051km
You have to divide 300 with 15, the answer to that is: 300/15=20. However, if she starts saving this week (counting as a first), she will have enough money in 19 weeks after the first week, she needs 20 weeks to save the money.