The average height of 3 boys was 156cm. When a girl joined them, the average height of the 4 children was 153cm. How tall was the girl?

The girl was 144cm tall

Step-by-step explanation:

Total height of the three boys=3×156=468

Total height of the four children=4×153=612

Height of the girl=612-468=144cm

(23*2)-12=x     x=34

step-by-step explanation:

1 number

if we use a graphing calculator, there is only one such number that satisfies the conclusion of the mean value theorem, that is, a number such that

where the right-hand side is the average rate of change of f on the interval [0.5,0.75], which is the slope of the secant line.

in the attached graph, the black line is the secant line which has its slope as the average rate of change of f on [0.5,0.75], while the orange line is the only tangent line to the graph of f in the interval that satisfies the mvt conclusion.