HOW TO TAKE HALF OF ANY NUMBER

PROBLEMS

Do the problem yourself first!

21.   In each column, calculate half of each number mentally.

 21.  1  ½ 10  5 100  50 21.  2  1 20  10 200  100 21.  3  1½ 30  15 300  150 21.  4  2 40  20 400  200 21.  5  2½ 50  25 500  250 21.  6  3 60  30 600  300 21.  7  3½ 70  35 700  350 21.  8  4 80  40 800  400 21.  9  4½ 90  45 900  450

22.   Calculate half mentally.

 22.  a)  11  5½ b)  15  7½ c)  17  8½ d)  21  10½ 13  e)  23  11½ f)  29  14½ g)  33  16½ h)  57  28½ 13.  i)  28  14 j)  36  18 k)  52  26 l)  114  57 13  m)  130  65 n)  350  175 o)  560  280 p)  770  385 22  q)   7.90  3.95 r)   14.70  7.35 s)   15.30  7.65 t)   25.20  12.60

23  a)  Two and a half times \$9.00 = \$18.00 + \$4.50 = \$22.50

23.  b)  Three and a half times \$7.00?  = \$24.50

23.  c)  Four and a half times \$11.00?  = \$49.50

23.  d)  Six and a half times \$5.00?  = \$32.50

24.  How much is a fourth or a quarter of these?  (Take half of half.  What
24.  percent is this?  25% )

 a)  64  16 b)  52  13 c)  56  14 d)  92  23 e)  \$1.08  \$.27 f)  \$6.12  \$1.53 g)  \$10.32  \$2.58 h)  \$18.04  \$4.51

25.  How much is 25% of these?

 a)  \$9  \$2.25 b)  \$14  \$3.50 c)  \$21  \$5.25 d)  \$50  \$12.50 e)  \$10.40  \$2.60 f)  \$60.20  \$15.05 g)  \$104.32  \$26.08 h)  \$216.28  \$54.07

26.  a)  How many seconds are there in a quarter of a minute?
10.  a)  (1 minute = 60 seconds) 15

26.  b)  How many seconds are in three quarters of a minute?  45

27.  Multiplying by 5.  Take half the multiplication by 10.

 17.  5 × 24 = 120 5 × 18 = 90 5 × 141 = 705 27.  5 × \$5.40 = \$27 5 × \$68.20  = \$341 5 × \$30.50 = \$152.50

28.  How much is 5% of

 a)  \$44?  \$2.20 b)  \$18?  \$.90 c)  \$68?  \$3.40 d)  \$150?  \$7.50 e)  \$127?  \$6.35 f)  \$325?  \$16.25

29.  You invest \$4,000 in a fund that earns 5% interest each year.  If you
24.  leave the money in the fund and do not touch it, then at the end of
24.  two years, how much money will you have?

(Compare Problem 24, Lesson 4. Compound interest..)

\$4,410.  For, at the end of the first year, you will have earned 5%, or \$200, in interest, so that you now have \$4,000 + \$200 = \$4,200.  At the end of the second year, 5% of that is \$210. You now have \$4,200 + \$210 = \$4,410.

30.  Multiplying by 15.

13.  a)  15 × 12 = 180  b)  15 × 16 = 240

18.  c)  15 × 24 = 360  d)  15 × 46 = 690

31.  How much is 15% of

19.  a)  \$20?  \$3  b)  \$30? \$4.50   c)  \$18?  \$2.70

19.  d)  \$40? \$6   e)  \$60?  \$9   f)  \$70?  \$10.50

Continue on to the next Lesson.

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