18M.1.SL.TZ2.T_3

pestleMathematicsAASLPaper 118M· sl-1-1-using-standard-formsource ↗

Last year a South American candy factory sold 4.8 × 10⁸ spherical sweets. Each sweet has a diameter of 2.5 cm.

The factory is producing an advertisement showing all of these sweets placed in a straight line.

The advertisement claims that the length of this line is x times the length of the Amazon River. The length of the Amazon River is 6400 km.

Find the length, in cm, of this line. Give your answer in the form a × 10^k , where 1 ≤ a < 10 and k ∈ $\mathbb{Z}$ .

[3]

Write down the length of the Amazon River in cm.

[1]

b.i.

Find the value of x.

[2]

b.ii.

Markscheme / solution

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

4.8 × 10⁸ × 2.5 (M1)

Note: Award (M1) for multiplying by 2.5.

1.2 × 10⁹ (cm) (A1)(ft)(A1)(ft) (C3)

Note: Award (A0)(A0) for answers of the type 12 × 10⁸.

[3 marks]

640 000 000 (cm) (6.4 × 10⁸ (cm)) (A1)

[1 mark]

b.i.

$\frac{{1.2 \times {{10}^9}}}{{6.4 \times {{10}^8}}}$ (M1)

Note: Award (M1) for division by 640 000 000.

= 1.88 (1.875) (A1)(ft) (C3)

Note: Follow through from part (a) and part (b)(i).

[2 marks]

b.ii.

Examiners’ report

[N/A]

b.i.

[N/A]

b.ii.