Answer:
Explanation:
This is a rate problem so using ratios is a good way to calculate the answer for different areas or amounts
675 g per 18 m² 675/18 g/m²
a) How many grams for 11m²
675/18 g/m² = ??? / 11 m² i cross multiply 675 times 11 divide by 18
or more simply multiply both side by 11
solving for the ???
(675)(11) g m² / 18 m² = ??? g = 412.5 grams ( the m²/m² cancel)
b) what area can be fertilised with 862.5 g? again applying ratio
this time we know the g and want to calculate an unknown area
675 / 18 = 862.5 / ??? this will take one more step since the ??? is
in the denominator
18 / 675 = ??? / 862.5 I just inverted both sides
18m² / 675g = ??? / 862.5g again simply multiply both sides by 862.5g
(18m²)(862.5g) / (675g) = ??? this time the grams cancel leaving m²
??? = 23 m²