The following chart indicates the reductions in total losses due to theft if a jewelry store hires additional security guards.
Number
Dollar Value of
of Guards
Thefts Prevented
1
150
2
240
3
310
4
360
5
400
6
430
If the security guards can be hired for $45 per day, how many guards should the shop hire?

A. 2.
B. 3.
C. 4.
D. 5.

Answer: C