Question

SOLVE THIS: 8400(1+r²/10000+2r/100)-8400-168r =21
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Answer 1

Answer:

8400+8400r²/10000+16800r/100-8400-168r=21

8400+84r²/100-8400=21

84r²/100=21

r²=21*100/84

r²=400

r=20