10. A banker counts 128 notes in the first minute and there after he counts half the number of notes
he counted in the previous minute. How many notes he would count in five minutes?
Answers
Answered by
1
Answer:
128+128×4÷2=256 the total note he counted is 256
Answered by
1
Answer:
248
Explanation:
a= 128
r= 1/2 (given that it count half notes in next minute)
n=5
sum of n terms= a[1-r^n]/[1-r]
=128*[1-(1/2)^5]/(1-1/2)
=128*[ (2^5-1)/2^5]/(1/2)
=128*2* [32-1]/32
= 4*2* 31
= 31*8
= 248 notes
verification:
128+64+32+16+8= 248
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