Why Does Coulomb's Law Give Different Results for the Same Charges?

[anna sung]

Homework Statement

three objects carrying charges of (a)-4x10^-6 C, (B)-6x10^-6 C, and (c)+9x10^-6 C are placed in a line equally spaced from left to right by a distance of 0.5m. calculate the magnitude and direction of the net force acting on each.

Homework Equations

Force of the magnitude of B(-6x10^-6 C) the answer is 1.08N left
but I am getting 2.8N right

The Attempt at a Solution

Fba= 0.864 N (right)
Fbc = 1.944 N (right)

fnet = 0.864N (right) + 1.944N (right)
= 2.8N right

i don't understand how the book got 1.944N (left) because that's what gives 1.08(left)

B is negative and C is positive so shouldn't B be attracted to C which is to the right?
please help me .

 

[PeterO]

Homework Statement

three objects carrying charges of (a)-4x10^-6 C, (B)-6x10^-6 C, and (c)+9x10^-6 C are placed in a line equally spaced from left to right by a distance of 0.5m. calculate the magnitude and direction of the net force acting on each.

Homework Equations

Force of the magnitude of B(-6x10^-6 C) the answer is 1.08N left
but I am getting 2.8N right

The Attempt at a Solution

Fba= 0.864 N (right)
Fbc = 1.944 N (right)

fnet = 0.864N (right) + 1.944N (right)
= 2.8N right

i don't understand how the book got 1.944N (left) because that's what gives 1.08(left)

B is negative and C is positive so shouldn't B be attracted to C which is to the right?
please help me .

As you realize, the only way to get that is if the charge on C is the same sign as the charge on B.
Either you have mis-read, or they have mis-printed.