Page 108 - Start Up Mathematics_5
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2.  Find the following products.

                  (a)  8.37 × 4           (b)  0.063 × 2          (c)  15.49 × 8          (d)  1.076 × 11
                  (e)  6 × 4.5             (f)  9 × 13.08         (g)  22.3 × 7.5         (h)  60.05 × 13.7
                   (i)  93.12 × 8.41       (j)  5.264 × 8.9       (k)  168.27 × 3.6        (l)  31.29 × 8.7

              3.  Fill in the blanks.
                  (a)  83.15 × 10 = _________                   (b)  6.0023 × 100 = _________

                   (c)  122.75 × 10 = _________                 (d)  9.3847 × 1,000 = _________
                  (e)  76.632 × 100 = _________                 (f)  45.086 × 1,000 = _________
                  (g)  9.534 × 10 = _________                   (h)  89.7049 × 100 = _________

              4.  Multiply.
                  (a)  41.6 × 2.3 × 7               (b)  6.81 × 7.04 × 10          (c)  21.9 × 6.52 × 4.1

                  (d)  92.34 × 3.5 × 6 × 8.2        (e)  100 × 74.681 × 5.3        (f)  7.98 × 3.24 × 6.5

            Division

            Division by a whole number

            Division of decimal numbers is similar to that of whole numbers with a difference that the
            decimal point is placed appropriately as it is clear from the steps given in the following example.
            Example 11:  Divide 12.5 by 5.
                                      .
            Solution:          5   1 2 . 5      Step 1:  Place the decimal point of the quotient just above
                                                        the decimal point of the dividend.
                                     2 . 5      Step 2: Now divide like whole numbers.
                               5   1 2 . 5
                                – 1 0   ↓
                                    2   5
                                  –  2  5
                                        0         So, 12.5 ÷ 5 = 2.5

            Example 12:  Find 1.762 ÷ 2.

                                   0 . 8 8 1                                      Maths Fun
            Solution:          2   1 . 7 6 2

                                – 0   ↓                                            What mathematical symbol
                                  1  7                                             can be put between 6
                                – 1  6                                             and 9, to get a number
                                                                                   bigger than 6 and
                                      1 6                                          smaller than 9?
                                  –  1 6
                                       0 2
                                     –   2
                                         0        So, 1.762 ÷ 2 = 0.881




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