apply formula to array, then COUNT

G'day,
I'm a farmer using excel via GOOGLE SHEETS to keep records on our cattle grazing grass business.
I have a set of animal weights (kg) going over several columns.
I have used the COUNTIF function to give me the results below showing the number of animals that fall into these different weight ranges ...... eg =COUNTIF(B:G,">=300")-COUNTIF(B:G,">339")

I also need the number of animals in these different weight ranges for their FUTURE PREDICTED weight ... ie, data set + (days * daily weight gain kg/day) .... then results arranged as per below.

COUNTIF doesn't seem to be able to handle this extra calculation ..... =(COUNTIF(B:G,"+(K29*K30)<=300")-(COUNTIF(B:G,"(+K29+K30)<=339")) ... doesn't work.

How else might I be able to achieve this?
I hope this makes sense. Thank you for your help!


weight range Number of animals
<=220kg 59
220 - 259 kg 58
260 - 299 kg 25
300 - 339 kg 12
340 - 379 kg 1
380 - 419 kg 1
420 - 439 kg 0
440 - 479 kg 0
480 - 519 kg 0
520 - 559 kg 0
560 - 600 kg 0
>=600kg 0

Thankyou. See attached worksheet. The cells I am having trouble with are colored yellow. Thanks again.

Try, using COUNTIFS
J35: =COUNTIFS(B:G,"<"&220-J28*J29)
J36: =COUNTIFS(B:G,">="&220-J28*J29,B:G,"<="&259-J28*J29)