For bonds, assume coupons paid semi-annually, coupon rates and yields quoted with semi-annual compounding, and redeemable at par unless otherwise noted

- A family wishes to accumulate $300,000 in a college education fund at the end of 15 years. If they deposit $10,000 in the fund at the end of each of the first 10 years and $10,000 + X at the end of each of the last five years, find X if the fund earns 5% effective.