The mean of 14 numbers is 49. Removing one of the numbers causes the mean to decrease to 43. What number was removed?

126 was removed.

Step-by-step explanation:

The total before division took place was

Total = mean * 14

mean = 49

Total = 49 * 14

Total = 685

Now you subtract x from the total

685 - x

And divide by 13 [one number is missing]

(685 - x)/13

and the result = 43

(685 - x ) / 13 = 43                Multiply both sides by 13

685 - x  = 43 * 13

685 - x = 559                       Subtract 685 from both sides

- x = - 126                             Multiply by - 1

x = 126

1 is c

2 is a

3 is a

step-by-step explanation:

c.   x=2.4cm

step-by-step explanation:

similar triangles are triangles which have the same shape but not the same size. this means their angle measures are equal but their side lengths are not instead they are proportional. to solve, we will set up a proportion and solve.

a proportion is two equal ratios set equal to each other. we form the ratios by finding corresponding sides (sides which match to each other on both triangles by their position). out ratios will be one side of the small triangle over the corresponding side on the big triangle as shown below:

.

to solve the proportion, we'll cross multiply by multiplying numerator with denominator across the equal sign.