I dont know direct way using blocks ... but you can use custom code block for calculating ...
https://fxdreema.com/shared/Z3FcRhufc
you can change math in code for your purposes ...
import it into your project to view which are constants and which are variables ...
0_1485624572602_upload-cdb2bf0f-6852-4d98-8674-61510c897259
0_1485624583409_upload-e33f5810-d96f-4193-bc4b-df921d4b1cf4
0_1485624623947_upload-6c77eacc-59c5-4ebd-ab8f-20187a5208e0
or simplier:
0_1485624821256_upload-8b107e5d-ba9d-479f-8031-068bf9daafc6