Δ Means Change

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Photo by Joshua Hoehne on Unsplash

Pop Quiz

1.

a. The average woman has 350,000 ova (eggs) by the time she starts menstruating but has shed 90% of those by the time she turns 30. Assuming you started with the average number of ova and you’re 30 now, write a formula you could use to calculate the number of ova you have left.

b. If your monthly fecundity rate (chance of conceiving per month) is 25% when you’re 20 years old but 10% once you turn 35, and one in four known pregnancies ends in loss before 12 weeks’ gestation, what are the odds of an individual ovum becoming a viable pregnancy at age 20? At age 35?

c. If menopause starts at age 51 and you are 30 now, how many times do you need to have procreative sex before an individual ovum becomes a viable pregnancy?

2.

For this question, assume that you have 25 female friends that are within 5 years of you in age. If 60% of them have already had one baby, 20% have had two, and 10% have had three, what is the total number of children that have been born? Show your work.
Extra credit: How far behind are you?

3.

x = y + 35
If your doctor tells you to expect to gain up to 35 pounds over the course of your pregnancy and y is your current weight, how foreign will your body feel to you when you have to buy maternity clothes?

4.

a. Assuming an annual net salary of $50,000 (the national average for a 25- to 34-year-old female college graduate), how much money would a woman in the US lose during 12 weeks of unpaid maternity leave (the only federally mandated parental leave) compared to a woman in Sweden making an equivalent salary whose maternity leave is 480 days paid at 80%? Answer in dollars.

b. An American woman who takes five years off from the workforce to care for a child can expect a lifetime career earnings reduction of 19%. Assuming lifetime earnings of $1,280,000 (median earnings for a college graduate), calculate the wages you would lose by taking a five-year career hiatus.

c. Assuming the US’s national average cost of full-time daycare for an infant ($1,200/month) calculate the cost of daycare per year. Then, using your answer to 4b, determine which is more expensive: a five-year career hiatus or five years of full-time daycare.

d. If your annual net salary is $50,000 and your partner’s annual net salary is $70,000, use your results above to calculate the percentage of your household income that childcare will represent. Answer in dinners out, romantic vacations, pedicures, lattes, hardcover books, or any other thing that you currently spend your disposable income on.

e. If a typical workday is 8 hours long, what percentage of that time will you spend wishing you were with your baby instead?

5.

a. x - y = Δ
In the equation above, where x represents your life as it is now and y represents everything you stand to lose if you decide to have a baby, solve for Δ.
Hint: y=(sleep)(sex)(focus)(your childfree friends)(money)(money)(money)(career growth)(time with your partner)(ten months of sushi, soft cheese, deli meat, and gin)(your favorite jeans)(your perky boobs)(wild Friday nights)(slow Sunday mornings)(your sense of self)(your future plans)(your freedom)(your heart)

b. x + z = Δ
Assuming x carries the same value as in problem 5a, but here z represents everything you stand to gain, solve for Δ.
Hint: z=(the first ultrasound)(first kick)(first look)(first smile)(first laugh)(first word)(the way your partner will laugh as you fold tiny onesies together)(a new name)(the rush of birth)(an appreciation for all of the things your body can do)(the delight of nurturing someone so small and sweet)(a stubborn hope that the world can get better)(will be better)(that you can make it better)(thousands of happy photographs)(delirious joy)(unending growth)(love)(love)(love)(love)

c. x - y + z = Δ
Solve for Δ.

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