The mass of pebbles in a packet is 650 g.
(A) janet needs 18 packets of pebbles to decorate her garden. What is the mass of pebbles that Janet needs? Give your answer in kilograms
(B) Malar needs 2.5 kg of pebbles to decorate an aquarium. How many packets of pebbles does Malar need?
(A) To find the mass of pebbles that Janet needs, we need to multiply the mass of one packet (650 g) by the number of packets (18):
650 g * 18 = 11700 g.
Since there are 1000 grams in a kilogram, we can convert grams to kilograms by dividing by 1000:
11700 g / 1000 = 11.7 kg.
Therefore, Janet needs 11.7 kg of pebbles.
(B) To find the number of packets of pebbles that Malar needs, we need to divide the desired mass (2.5 kg) by the mass of one packet (650 g):
2.5 kg / 0.65 kg = 3.846.
Since packets can't be divided into smaller fractions, Malar would need to round up to the next whole number. Therefore, Malar needs 4 packets of pebbles.