Lesson 4
Practice Makes Perfect
Prowess with powers
Page 146
Your answer :
1(21) + 1(20) + 1(2 − 1)
= 3(1)/(2)
7(103) + 6(102) + 4(101) + 2(100)
= 7, 642
2(72) + 3(71) + 4(70)
= 123
1(8 − 1) + 2(8 − 2)
= (10)/(64)
⎫⎪⎪⎬⎪⎪⎭ This set contains a mistake.
Well, let’s see:
1(21) + 1(20) + 1(2 − 1)
= 1(2) + 1(1) + 1⎛⎝(1)/(2)⎞⎠
= 2 + 1 + (1)/(2) = 3(1)/(2);
7(103) + 6(102) + 4(101) + 2(100)
= 7(1000) + 6(100) + 4(10) + 2(1)
= 7000 + 600 + 40 + 2
= 7, 642;
2(72) + 3(71) + 4(70)
= 2(49) + 3(7) + 4(1)
= 98 + 21 + 4 = 123;
1(8 − 1) + 2(8 − 2)
= 1⎛⎝(1)/(8)⎞⎠ + 2⎛⎝(1)/(82)⎞⎠
= 1⎛⎝(1)/(8)⎞⎠ + 2⎛⎝(1)/(64)⎞⎠
= 1⎛⎝(8)/(64)⎞⎠ + 2⎛⎝(1)/(64)⎞⎠
= (8)/(64) + (2)/(64) = (10)/(64).
No mistakes here. Return to page 129 and try again.
