Page 173 - Calculating Agriculture Cover 20191124 STUDENT - A

CH 15] Calculating Agriculture 15-1

NOTE TO INSTRUCTOR: Solutions
CHAPTER 15 to Homework are in that section.

Avg. time for Students to read &
complete homework: 1.5 hrs.

Metric Measurements

Objectives

After mastering the material in this chapter, you will be able to:

 Understand the differences in Metric and English measurements
 Solve Problems written with metric measurements
 Convert English measurements to equivalent metric measurements
 Convert metric measurements to equivalent English measurements
 Use the metric prefixes for length, area, weight and volume

A System of Measurement

Your reading and calculations in the prior chapters have been with English measurements. In this
chapter a discussion on the Metric System (SI) of measurement will ensue. Learners are often
presented with problems that contain both English and metric measurements and asked to solve the
problem (present their answer) as either an English or metric value. This creates a dilemma and
confusion because the learner needs to either convert the metric measurement to English or the
English measurement to metric prior to resolving the solution. This conversion step prior to solving
often leads to wrong solutions even though the algorithm is the same as you have studied. It is best to
begin and end a solution in either metric or English and then convert the answer to either its English or
metric equivalent if that is what is asked for; which means that the problem must be stated, set up, as
either English or metric and NOT a combination of English and metric.
In this chapter examples will be referenced to the chapter and page number that they originate 15
from, as you have already worked through them and are familiar with them.

Refer to pages 10-15 & 10-16
Example English A: Harvesting 240,000 lbs of grain at 22% moisture and the desired dried
moisture will be 15%. (a) Calculate the absolute dry matter for this harvest,
(b) the weight for the grain after being dried to 15%.
Solution
(a) Wet Weight % – Moisture % = Dry Matter %
100% − 22% = 78%
Total Wet Weight x Dry Matter % = Dry Matter
240,000# x 78% =
240,000# x 0.78 = 187,200#

(b) Wet Weight % – Moisture % = Dry Matter %
100% − 15% = 85%
Dry weight = Dry Matter ÷ Dry Matter %
= 187,200 # ÷ 85%
220,235.29 # = 187,200 # ÷ 0.85 (at 15% desired moisture)

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