Question

Study the pattern and write next step:
$85\times \left(9\right)=85\times (10-1)=765$
$85\times \left(99\right)=85\times (100-1)=8,415$
$85\times \left(999\right)=85\times (1000-1)=84,915$

• A. $85\times \left(9\right)=85\times (10+1)=765$
• B. $85\times \left(9\right)=85\times (100-1)=765$
• C. $85\times \left(9999\right)=85\times (10,000-1)=849,915$
• D. $85\times \left(9999\right)=85\times (10-1)=884,915$

Answer 1

The correct option is C $85\times \left(9999\right)=85\times (10,000-1)=849,915$

$Now85\times \left(9\right)=85\times (10-1)=76585\times \left(99\right)=85\times (100-1)=8500-85=841585\times \left(999\right)=85\times (1000-1)=85000-85=8491585\times \left(9999\right)=85\times (10000-1)=850000-85=849915$