Question

f) 7×(50-2) 4-7-7-7-77-7-77777-​

Answer 1

120.75

I think this is the right answer

Answer 2

$●\large\sf \bf \underline\pink{ your\: \: answer \: !!}$

[9 +99 +999+....

[9 +99 +999+....terms]

[9 +99 +999+....terms]= [(10 − 1) + (100 − 1) + (1000 − 1) - - .+ to n term] +

[9 +99 +999+....terms]= [(10 − 1) + (100 − 1) + (1000 − 1) - - .+ to n term] += [10+100+1000+ n terms - ( 1+1+1+1+.. n terms)

[9 +99 +999+....terms]= [(10 − 1) + (100 − 1) + (1000 − 1) - - .+ to n term] += [10+100+1000+ n terms - ( 1+1+1+1+.. n terms)7 9 [10+100+1000+. terms -n] .n

[9 +99 +999+....terms]= [(10 − 1) + (100 − 1) + (1000 − 1) - - .+ to n term] += [10+100+1000+ n terms - ( 1+1+1+1+.. n terms)7 9 [10+100+1000+. terms -n] .nHere a = 10, r = 10

[9 +99 +999+....terms]= [(10 − 1) + (100 − 1) + (1000 − 1) - - .+ to n term] += [10+100+1000+ n terms - ( 1+1+1+1+.. n terms)7 9 [10+100+1000+. terms -n] .nHere a = 10, r = 107 [10(10¹ - 1) 9 [10(100) n

[9 +99 +999+....terms]= [(10 − 1) + (100 − 1) + (1000 − 1) - - .+ to n term] += [10+100+1000+ n terms - ( 1+1+1+1+.. n terms)7 9 [10+100+1000+. terms -n] .nHere a = 10, r = 107 [10(10¹ - 1) 9 [10(100) n70 81 = (10⁰ - 1) – n - -

[9 +99 +999+....terms]= [(10 − 1) + (100 − 1) + (1000 − 1) - - .+ to n term] += [10+100+1000+ n terms - ( 1+1+1+1+.. n terms)7 9 [10+100+1000+. terms -n] .nHere a = 10, r = 107 [10(10¹ - 1) 9 [10(100) n70 81 = (10⁰ - 1) – n - -+ to n