Question

On 1st November Priya has 200 sweets in a box. She eats no sweets first day and she eats 8 sweets per day from the box thereafter. On what day of the month will she have 40 sweets left? Show your calculations using the formula for Tn of an arithmetic sequence

Answer 1

Answer:

Priya has 200 sweet

she eats none on first day

She eats 8 sweet per day

so by Subtracting and multiplying

on 21 Of November she has left 40 sweets

Answer 2

Answer:

n-1=20

Step-by-step explanation:

a1= 200

a2=192

d=-8

an=40

an= a+(n-1)d

40= 200+(n-1)(-8)

-160=n-1(-8)

20=n-1

n=21

Since she eats no sweets on the first day we should consider n-1=20 as the answer