Maths Maths Puzzle Numerical Ability

What is the sum of the following using the formula for an arithematic series.40+42+44+....+68.

Read Solution (Total 3)

((68(68+1)) - (38(38+1))
8 years agoHelpfull: Yes(0) No(0)

n+2
40+2=42
42+2=44
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66+2=68
8 years agoHelpfull: Yes(0) No(0)
Ap=n/2(a1+an)
15/2(40+68)=810
6 years agoHelpfull: Yes(0) No(0)

Maths Other Question

A contractor takes a contract of a work for 40 days & initially he appointed 100 men on the job. After 35 days he appointed 100 more person on the job & finished the work on time. If he doesn't appoints more workers on a job the how many days work will take to complete from actual time? Use the arithematic sequence of numbers 2,4,6,8,10.....to find the sum of the first 20 terms.?