to calculate

https://tts.langeek.co/read?text=dG8gY2FsY3VsYXRl&hash=6f6195c0cc72d1b4f0b7b4bf41c2b683fbfda335&lang=en&cache-only=0&driver=googletts

Here you will find the vocabulary from Unit 10 in the Headway Intermediate coursebook, such as "fall out", "develop", "save up", etc.