Financing by Debt

In June 2018:
Tin Co needs to raise $2m.
If debt is used, Tin Co will issue 20,000 8% loan notes with a nominal value of $100 per loan note.

In September 2020:
Spine Co is looking to spend $15m to expand its existing business.
If debt is chosen, the company will issue $15m of 8% loan notes at their nominal value of $100 per loan note.

When calculating the Finance Charges, in the answers they are worked out differently:

For Tin Co it is 20,000 x 8% x $100 = 160,000

For Spine Co it is 15m x 8% = 1.2m

Why is the nominal value of $100 used in Tin Co, and not used in Spine Co?

Thank you.