Life of Fred question

[6kids2luv]

I am considering getting the Life of Fred Fractions & Decimals/Percents books, and am wondering is there answer keys with them? And, for those of you who combined them with Singapore, what level of Singapore did you start Life of Fred in?
Thanks for your help!

[matroyshka]

The answers are right in the book.

My kids did LOF Fractions after Singapore 4B, and I'm planning on having them do Decimals/Percents next summer after 5B. I'm sure it could be done concurrently, but I'm planning on using it for "fun math" to keep things fresh over the summer, so no rush.