Jack currently earns $14,000 he wants to earn $60,000 a year
To increase his current earnings of $14,000 to $60,000 a year, Jack needs to increase his income by $60,000 - $14,000 = $<<60000-14000=46000>>46,000 per year.
Since there are 12 months in a year, Jack needs to increase his income by $46,000/12 = $<<46000/12=3833.33>>3,833.33 per month.
Therefore, Jack needs to find additional sources of income or a new job that pays at least $3,833.33 per month to reach his goal of earning $60,000 a year.