The names PNM and MPN are perfectly valid. The order of the letters doesn't matter. In fact, there are 6 ways to name this plane if we just use the 3 letters. If we include "plane Z", then there are 7 total ways to name the plane.
For some reason, your teacher wants P to be the third letter as s/he mentioned MNP and NMP. But again, the order doesn't matter.
50+0.05x-25=20+0.06x-12
Solve algebraically <span />
23% off is 46 because 10%is 20 so 20% is 40 and 1% is 2 because 20/10 is 2 so the answe is 46