Answer:

Step-by-step explanation:
The LCM of 14, 21 and 6 is 42
We require to change the fractions to fractions with a denominator of 42
+
+ 
=
+
+
← add the numerators, leaving the denominator
= 
=
← divide both values by 2
=
← in simplest form
Answer:
10
Step-by-step explanation:
1x2x2.5=5
5/0.5=10
3x7 + 2x3 = 22 + 6 = 28 is the area
Answer:
the first one is 4 and 5
Step-by-step explanation:
the second one is 45 because 15+15+15 is 45, you get 15 by the square root of 225