Multiplying 0.7 by the original price will work...
If you divide the cost by 100, subtract 30 from 100, you will be left with 70% times the 1/100
70% is also expressed as 0.7, since 7/10=70/100
Hope this helps!
Place your dot roughly around 2.23. The square root of 5 is 2.23
The two long sides are 63meters and the shorter sides are 21meters.
There ar 4persons so each will pay

Only two persons have spent more money than everyone average i.e mia and Jasmin.
Now
- Mia has-28.47
- Jasmin has=20.99
Mia left more money so she saved most money.