First, we are going to multiply the pieces of wood by the length of each piece to find the total length she will need:
[tex]78*29cm=2262cm[/tex]
Next, we are going to convert 2262 centimeters to meters. To do that we are going to take advantage of the fact that 1 m=100cm:
[tex]2262cm* \frac{1m}{100cm} =22.62m[/tex]
Now, we just need to divide the total length of wood Marguerite needs by the length of each board of wood:
[tex] \frac{22.62m}{6m} =3.77[/tex]
Since she will need full boards of wood, we must round 3.77 to its nearest integer 4.
We can conclude that Marguerite will need 4 boards of wood.