👤

un excavatorist are de sapat un sant in trei zile .In prima zi el sapa 98m, iar in celelante zile sapa in fiecare zi cu 9m mai mult decat in ziua precendenta. Cati metri a sapat excavatoristu?

Răspuns :

a=98 m in prima zi
b=98+9=107 m in a doua zi
c=107+9=116 m in a treia zi

a+b+c=98+107+116=321 m a sapat in cele trei zile
98m+9m=107m (in a 2 zi)
107m+9m=116m(in a 3 zi )
98m+107m+116m=205m+116m=321m (in total)