To solve this formula for T, divide both sides of the original equation by PR:
I PRT
------ = --------- => T = I / (PR)
PR PR
Please note: Because the formula I = PRT involves neither addition nor subtraction, the final formula for T cannot involve either addition nor subtraction. That leaves:
T = I P/R
T= IPR
The second formula here is incorrect; we cannot solve I = PRT for T simply by rearranging the order of the variables. This leaves T = I P/R as a possible answer, but this answer does not agree with my T = I / (PR). Please double check to ensure that you have copied down the four possible answers correctly.
Going by the time frame and date attached to this question, if school holidays should begin by Saturday 9 am, then from 1pm today we are 68 hours away from holiday.