Guess this is why they don’t call it the Mathematics Transportation Authority.

In a presentation to the MTA Board on Thursday morning, MTA Chief Financial Officer Bob Foran said that Gov. Cuomo’s controversial plan to hire 500 new MTA police officers will cost the agency $249 million over the next four years — partly financed by the $200 million the agency will save over that same period through those and other cops’ anti-fare evasion efforts.

The $249 million price tag was eye-popping to activists, given Foran himself warned of a $426-million deficit projected for 2023.

“Say we had $249M and we could do anything we wanted to improve the subway system, what would you want to see prioritized?” State Senator Jessica Ramos tweeted in reaction to the news.

And MTA Board member Veronica Vanterpool said that she couldn’t support the idea to hire the officers, which will be up for a vote, along with the entire 2020 MTA budget, at December’s board meeting. Vanterpool said she needed a better explanation for why the MTA police force had to grow from 666 uniformed officers to 1,114, especially in light of the current “Churro Crackdown” debacle — a fortnight of viral videos featuring multiple police brutality and churro arrest incidents. There are hundreds of NYPD officers also patrolling the subways.

“Before we [vote to] say this is the right number, we need to understand why it’s the right number, and ask if we’re using our resources in the most strategic way,” said Vanterpool, an appointee of Mayor de Blasio.

MTA Board member Sarah Feinberg, a Cuomo appointee, supports the hiring of additional cops, but could not provide a coherent reason for them. She said that overall crime numbers are down, but the MTA still had “a problem we have to address” because she said major crime numbers are up. Through October there were 6.51 major felonies per day on the subway system, compared to 6.67 per day in 2018 and 6.63 in 2017 — down 2.5 percent. And though here have been 36 more robberies this year — that’s also up only 5.8 percent.

Still, the governor wants to nearly double the size of the underground paramilitary police force.

Asked who came up with the need for 500 police exactly, Foye merely told reporters “that number was developed with the MTA police department and the agency,” and that the MTA also needed the police for the commuter railroads, though Foye would not say where the new officers would be deployed if they were hired.

Indeed, there’s a “pay no attention to that man behind the curtain” element of the current debate over the MTA’s police expansion bid. Foye, for example, said that the officers involved in this summer’s Fare Evasion Task Force blitz — which featured 200 from the NYPD and 300 reassigned MTA cops — are continuing their work. But then MTA spokesman Tim Minton said those NYPD and MTA Police would go back to their original assignments once the 500 new cops joined the MTA force — unless, of course, they don’t.

“In some cases, [police command] might decide we keep the surge in the subways. It’s conceivable the MTA police say we need fewer people in Stamford [a suburban Metro-North station] and more in the subways, but that’s a police management issue,” Minton said.

Amid all this spaghetti-throwing to rationalize Cuomo’s desire for 500 new cops, Foye even brought up the September 11 attacks and the threat of terrorism — an entirely new explanation that was missing from the original announcement of the 500-officer redeployment, missing from a subsequent announcement that the agency would hire 500 new police, and even missing from the latest reason given by gubernatorial spokeswoman Dani Lever.

“The initiative is to combat violent incidents including robberies and assaults on transit workers, and hate crimes,” Lever told Gothamist.