Hello, dumluck!

I'm not impressed with their explanation.

Q: Shawn invested one half of his savings in a bond

that paid simple interest for 2 years and received $550 as interest.

He invested the remaining in a bond that paid compound interest, compounded annually,

for the same 2 years at the same rate of interest and received $605 as interest.

What was the value of his total savings before investing in these two bonds?

. .

Let be the annual interest rate for both accounts.

Let be the amount invested inaccount.each

He invested dollars at percent simple interest for 2 years.

. . This earned: . dollars in interest.

So we have: . .[1]

He invested dollars at percent compounded annualy for 2 years.

. . This grew to: . dollars in two years.

His interest is: . dollars.

. . So we have: . .[2]

Substitute [1] into [2]: .

. . . . . .

Substitute into [1]: .

Hence, he invested inaccount.each

Therefore, he invested a total of