The first question we need to answer is how many minutes are in one year?
1 yr = 365 days
1 day = 24 hr
1 hr = 60 min.
So, 1 day = 24 * 60 = 1440 min. and
365 days = 365 * 1440 min.
Once you find the product of 365 * 1440, divide 4.2 million by that product.
You may find it easier to use scientific notation. Note that 4.2 million = 4.2 x 106
You can also write the product of 365 * 1440 in scientific notation and then perform the division.