USING LAYOUT TOOLS 8 th Grade Shop Skills

USING LAYOUT TOOLS 8 th Grade Shop Skills

System of Measurement • English – standard measurement in the United States, now called U. S. Customary System – Uses, inch, foot, yard, rod and mile as units – 12 inches in a foot – 3 feet in a yard – 16 ½ feet in a rod – 5, 280 foot in a mile

System of Measurement • Metric System – used for scientific work in the United States – Measurements are based on the meter – 1 Meter = 100 centimeters (cm) – 1 Meter = 1, 000 millimeters (mm) – 1000 Meters = a Kilometer (km) • Units are in multiples of 10

Inch as a Unit of Measurement • Traditional unit for woodworking and metalworking • Some fine rules or scales have 32 marks per inch. • Most rules have 16 marks per inch with each mark equaling 1/16 of an inch.

How To Read a Ruler • Identify how many marks there are to an inch. • Measure item and count how many marks past a whole number. • Reduce to least common denominator

Reading a Ruler • How many marks are there to an inch on this ruler? – 16

Reading a Ruler • Locate the marks for 1”, 2”, 3” and 4” • Inch marks are the longest, usually the number is located under or to one side of the line.

Reading a Ruler • Look at the lengths of the lines to determine measurement. – – – The longest line is for a whole number 1 Next longest line is for 1 /2 Next longest line is for 1 / 4 and 3 / 4 Next longest line is for 1 / 8, 3 / 8, 5 / 8 and 7 / 8 Remaining lines are 1/16, 3/16, 5/16, 7/16, 9/19, 11/16, 13/16, 15/16

Make Your Own Ruler • On the strip of paper given to you, write 0 on one end and 1 on the other. • Fold in half and draw line on the crease, write 1 / 2 at the crease. • Fold in half again. The creases created are 1 / 4 and 3 /4 • Fold in half again to get 1, 3, 5, 7 /8 th • Fold in half again to get 1, 3, 5, 7, 9, 11, 13, 15, 16 ths

Reading A Ruler • The Letter A represents what measurement? – 1”

Reading A Ruler • The Letter B represents what measurement? – 1 7/16”

Reading A Ruler • The Letter C represents what measurement? 1 14/16” or 1 7/8”

Reading A Ruler • The Letter D represents what measurement? 2 11/16”

Reading A Ruler • The Letter E represents what measurement? 3 1/16”

Reading A Ruler • The Letter F represents what measurement? 3 5/16”

ONLINE PRACTICE • http: //www. rickyspears. com/rulergame/ • http: //www. funbrain. com/measure/index. ht ml

Working With Fractions • What is a fraction? – It is a portion of a whole – They have a numerator (Top Number) – And a denominator (Bottom Number) – 1 / 2 would mean 1 part of 2

Working With Fractions Online • http: //www. visualfractions. com/Enter. Fracti on. html

Adding Fractions • With common (same) denominators – Add nominator – Denominators stay the same • ¼ + ¾ = 4/4 • 3/8 + 5/8 = 8/8 • 3/16 + 7/16 = 10/16

Adding Common Denominators • 1/4+1/4= • 1/8+5/8= • 2/4 • 6/8 • 3/4+3/4= • 3 / 16 + 3 / 16 = • 6/4 • 6 / 16 • 1/8+3/8= • 4/8 • 5/8+7/8= • 12 / 8 • 1 / 16 + 5 / 16 = • 6 / 16 • 7 / 16 + 5 / 16 = • 12 / 16

Adding Fractions Online • Add Fractions With Like Denominators using Circles

Adding Fractions • With uncommon (different) denominators – One or both fractions will need to changed so both will have a common denominator • 3/8 + 3/16 – First change 3/8 to 6/16 by multiplying both the numerator and denominator by 2 • 6/16 + 3/16 = 9/16

Adding Uncommon Denominators • 1/2+1/4= • 3/4 • 1/2+1/8= • 5/8 • 1 / 2 + 1 / 16 = • 9 / 16 • 1/4+1/8= • 3/8 • 1 / 4 + 1 / 16 = • 5 / 16 • 1 / 8 + 1 / 16 = • 3 / 16 + 1 / 2 = • 11 / 16 • 5 / 16 + 3 / 8 = • 11 / 16

Adding Uncommon Denominators • http: //www. visualfractions. com/Add. Unlike Circle. html

Reducing Fractions • Reduce fractions to their least common denominator. • Divide the numerator and denominator by the same number so both are whole numbers. • 4 / 8 = 1 / 2 (both 4 & 8 can be divide by 2) • 5 / 8 = 5 / 8 (cannot be divide and remain a whole number)

Reducing Fractions • http: //www. visualfractions. com/Lowest. Circ le. html • http: //www. learningplanet. com/sam/ff/index. asp

Adding Compound • 1 st Method – Convert the whole numbers to fractions and add like or common denominators • • 1 3/8+2 5/8= 11 / 8 + 21 / 8 = 32 / 8 = 4

Adding Compound Fractions • 2 st Method – Add the fractions together then add the whole numbers to the fraction • • • 1 3/8+2 5/8= 3/8+5/8= 8/8= 1 1+1+2=4

Adding Compound Fractions • http: //www. visualfractions. com/Add. Strict. Ci rcle. html

Subtracting Fractions • With common (same) denominators – Subtract nominator – Denominators stay the same • 3/4 - 1/4 = 2/4 • 5/8 - 3/8 = 2/8 • 7/16 - 3/16 = 4/16

Subtracting Common Denominators • 1/4 -1/4= • 5/8 -1/8= • 0/4 • 4/8 • 3/4 -3/4= • 3 / 16 - 3 / 16 = • 0/4 • 0/ 16 • 3/8 -1/8= • 2/8 • 7/8 -5/8= • 2/8 • 5 / 16 -1 / 16 = • 4/ 16 • 7 / 16 - 5 / 16 = • 2 / 16

Subtracting Fractions Online

Subtracting Fractions • With uncommon (different) denominators – One or both fractions will need to changed so both will have a common denominator • 3/8 - 3/16 – First change 3/8 to 6/16 by multiplying both the numerator and denominator by 2 • 6/16 - 3/16 = 3/16

Subtracting Uncommon Denominators • 1/2 -1/4= • 1/4 • 1/2 -1/8= • 3/8 • 1 / 2 - 1 / 16 = • 7 / 16 • 1/4 -1/8= • 1/8 • 1 / 4 - 1 / 16 = • 3 / 16 • 1 / 8 - 1 / 16 = • 1 / 16 • 1 / 2 - 3 / 16 = • 5 / 16 • 3 / 8 - 5 / 16 = • 1/ 16

Subtracting Uncommon Denominators

Subtracting Compound Fractions • 1 st Method – Convert the whole numbers to fractions and subtract like or common denominators • • • 2 5/8 -1 3/8= 21 / 8 - 11 / 8 = 10 / 8 = 1 2/8 1 1/4

Subtracting Compound Fractions • 2 st Method – Subtract the fractions then subtract the whole numbers then add results together – 2 5/8 -1 3/8= • • 5/8 -3/8= 2/8 2– 1=1 1 + 2 / 8 = 1 2 / 8 or 1 1/4