I honestly believe its D but I'm not for sure. Sorry if i didn't help much
53: 800 and 900
54: 700 and 800
55: 500 and 600
56: 2,771,100 and 2,771,200
57: 90,120,000 and 90,120,100
58: 631,900 and 632,000
59: 93,300 and 93,400
60: 200 and 300
61: 900 and 1000
62: 39,576,700 and 39,576,800
63: 24,900 and 25,000
64: 471,100 and 471,200
FOLLOW ME FOR CLEARING YOUR NEXT DOUBT
Let b be the base. Then
b+16=1/2 (6b)
3b=b+16
2b=16
b=8
☺☺☺☺
