# Teenager attempts to explain ‘girl math’ to her father: ‘Money in my app, it’s free’

A video of a teenage girl attempting to explain the concept of “girl math” to her father has gone viral.

On 30 August, Marley Brown - who goes by @thebobmarleyy on TikTok - posted part one of her four-part video series, explaining the recent cultural phenomenon to her father. In Brown’s first video, which has more than 1.6m views, she told her father that the first example of “girl math” was buying two concert tickets for her friends.

“If I buy concert tickets for two people, and those people pay me back, the money they pay me back for is free,” she jokingly explained. Brown noted that, since the money for the concert tickets had already left her bank account, that meant the money they returned to her was “free money”.

Immediately, her father began to shake his head in disagreement. “But then you just use the money twice,” he pointed out.

Brown went on to say, according to “girl math”, that returning an item and receiving the money back for it makes the returned cash also free money.

Each video in the series showed Brown going through a list of “rules” associated with “girl math”. However, part three of the series attracted a whopping 11.5m viewers due to the supposed “relatable” examples she used.

“If something’s less than \$5, it’s free,” Brown said, before her father responded: “No. What if you buy a hundred things that are \$4?”

She then admitted that using money in her Starbucks app to purchase a drink, which customers can do by transferring money from their bank account to the Starbucks app, means that it’s actually a no-cost beverage. “If I want to get Starbucks and there’s already money in the account, money in the app, it’s free,” Brown told her father. “Like, I’m not paying for that Starbucks.”

While Brown’s father corrected her by pointing out how she had already “loaned them money”, many individuals on TikTok sided with Brown.

“The Starbucks one is so real,” one TikToker commented.

According to Brown, the “girl math” phenomenon also applies to online shopping. For example, if a company offers free shipping for items more than \$10, it makes sense to purchase additional items in order to qualify for the free shipping.

“If the shipping is \$4, I should spend the \$10 because it’s a better investment,” Brown told her dad, to which he simply said: “No.”

Still, followers agreed with Brown, writing: “The free shipping one makes so much sense though because at least you’re paying \$10 for an item rather than \$4 for nothing.”