Answer:
8977
Step-by-step explanation:
Hello,
[tex]49+50+51+52+...+141+142\\\\=(48+1)+(48+2)+(48+3)+(48+4)+...+(48+93)+(48+94)\\\\=48\times 94+(1+2+3+4+...+93+94)\\\\=48\times 94 + \dfrac{94\times 95}{2}\\\\=47(48\times 2+95)=47\times 191=8977[/tex]
thanks
