2.
a)
100%+25%=125%
100%-850mln
125%-x
x=125%×850/100%=5×850/4=1062,5mln≈1 062 500 000[1981r]
100%+24%=124%
100%-1062,5mln
124%-x
x=124%×1062,5/100%=1317,5mln≈1 317 500 000[1991r]
100%+21%=121%
100%-1371,5mln
121%-x
x=121%×1271,5/100%=1538,515mln≈1 538 500 000[2001r]
b)
1317,5-1062,5=255mln
100%-1317,5
x-255
x=100%×255/1317,5=255 000/13175=19,3548387096%≈19%
