Question

The wheel of a toy car rolling up an inclined plane covers 30cm during the first, 27cm during the second and 24cm during the third and so on.How much distance covered in 10 seconds

Answer 1

we can see it sum of first 10 seconds

here,

a=30

n=10

d=a2 -a1 =27-30 = -3

sn =n/2 {2a + (n-1)d}

sn=5{60+(-27)}

sn=43×5=215

therefore,

distance covered in 10 sec is 215cm