The following formula can be used to calculate an estimate for blood alcohol content (BAC) for males - HSC - SSCE Mathematics Standard - Question 36 - 2023 - Paper 1

Substituting the known values into the BAC formula:

$0.02 = \frac{(10 \times 3) - 7.5H}{6.8 \times 75}$

Calculating the constants:

• $N = 3$ (standard drinks)
• $M = 75$ kg

The equation simplifies as follows:

$0.02 = \frac{30 - 7.5H}{510}$

Multiplying through by 510:

$0.02 \times 510 = 30 - 7.5H$

$10.2 = 30 - 7.5H$

Rearranging gives:

$7.5H = 30 - 10.2$

$H = \frac{19.8}{7.5}$

Calculating $H$:

$H = 2.64 \text{ hours}$