Depends on the condition. GM trucks do seems to crack sooner than most. IF cracks are present every 1/4" perpendicular to the grooves, pieces are missing, there are any cracks going the with the grooves, fraying on the edges is occuring. oil is present on the belt, then replace it. Otherwise, probably not. If it makes noise then that may case you to want to change it.
26000 increased by 30 percent =33800=26000 + (30% * 26000 )=26000 + (0.3 * 26000 )=26000 + 7800= 33800
26000
7% of 26000 = 7% * 26000 = 0.07 * 26000 = 1820
70% of 26,000= 70% * 26000= 0.7 * 26000= 18,200
26000
26000
26000
26000
26000
6 ÷ 100 × 26000 = 1560
2600 subtracted from 26000 = -23400
Exactly as in the question: 26000