(i) 0.0000000000085
To convert this small number into the standard form we need to move the decimal to its right by 12 steps.
\(= \frac{85}{10000000000000}\)
\(= 8.5 × \frac{10}{10¹³}\)
\(= 8.5 × 10^{-13} × 10\)
\(= 8.5 × 10^{-12}\)
∴ The standard form of a given number is \(8.5 × 10^{-12}\)
(ii) 0.00000000000942
\(= \frac{942}{100000000000000} \)
\(= 9.42 × \frac{10^2 }{ 10^{14}}\)
\(= 9.42 × 10^{−14} × 10^2\)
\(= 9.42 × 10^{−12}\)
∴ The standard form of a given number is \(9.42 × 10^{−12}\)
(iii) 6020000000000000
= 6.02 × 102 × 10000000000000
= 6.02 × 102 × 1013
= 6.02 × 1015
∴ The standard form of the given number is 6.2 × 1015
(iv) 0.00000000837
\(= \frac{837 }{ 100000000000}\)
\(= 8.37 × \frac{10^2 }{ 10^{11}}\)
= 8.37 × 10−11×102
= 8.37 × 10−9
∴ The standard form of a given number is 8.37 × 10−9
(v) 31860000000
= 3.186 × 103 × 107
= 3.186 ×1010
∴ The standard form of the given number is 3.186 × 1010
Fill in the blanks in the sentences below (the verbs given in brackets will give you a clue).
(i) The earth trembled, but not many people felt the ____. (tremble)
(ii) When the zoo was flooded, there was a lot of _____ and many animals escaped into the countryside. (confuse)
(iii) We heard with _____ that the lion had been recaptured. (relieve)
(iv) The zookeeper was stuck in a tree and his _____ was filmed by the TV crew. (rescue)
(v) There was much _____ in the village when the snake charmer came visiting. (excite)