We have,

To express periodic number calculated we use:

Hope this helps.
r3t40
Step-by-step explanation:
2x - 10y > -20
=> x - 5y > -10
or x - 5y +10 > 0
Answer:
1.thursday
his expenses was p26.85
2.monday he spent p40.8
3.18.90+23.15+11.80+16.35+9.20=approximately p55.6×30 days=p1,668
4.693.80-1,668
so he savings is completely enough