Answer:
Estimated amount of pencils = 2040 pencils
Exact amount of pencils = 2160 pencils
Step-by-step explanation:
Estimated amount of pencils are calculated by:
rounding up the numbers to the nearest tens
large box= 144 pencils = 140 pencils
small box = 24 pencils = 20 pencils
Estimated number of pencils =
(12 × 140) + (18 × 20)
= 1680 + 360
= 2040 pencils
This is an underestimate
The exact number of pencils is calculated as:
(12 × 144 pencils ) + (18 × 24 pencils)
= 1728 pencils + 432
= 2160 pencils